HAFNIUM-Microsoft-Exchange-0day

Cool Resources CheckMyOWA What is it? We set up this site to aid victim notification based on lists of compromised Exchange servers with Outlook Web AccessOWA enabled, which were obtained from perpetrators of this mass breach event. This includes affected IPs/domains, as well as whether the actor...

HAFNIUM-IOC

HAFNIUM-IOC Hafnium-IOC is a simple PowerShell script that runs on Exchange servers to identify indicators of compromises IOCs from the Hafnium activity release by Mircosoft on 2021-03-02 https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/. The script may be...

Zirconium

ZIRCONIUM ZIRCONIUM has been created to scan for Indicators of Compromise IOCs on Exchange Servers for signs of Zero-Day exploits used by HAFNIUM. ZIRCONIUM will search for: CVE-2021-26855 CVE-2021-26958 CVE-2021-26857 CVE-2021-27027065 Suspicious .dmp Files .aspnet Files Found in inetpub and...

Chinese Silk Typhoon Hacker Extradited to U.S. Over COVID Research Cyberattacks

A Chinese national accused of being a member of the Silk Typhoon hacking group has been extradited to the U.S. from Italy. Xu Zewei, 34, was arrested in July 2025 by Italian authorities for his alleged links to the Chinese state-sponsored threat group and for orchestrating cyber attacks against...

Chinese Hacker Xu Zewei Arrested for Ties to Silk Typhoon Group and U.S. Cyber Attacks

A Chinese national has been arrested in Milan, Italy, for his alleged links to a state-sponsored hacking group known as Silk Typhoon and for carrying out cyber attacks against American organizations and government agencies. The 33-year-old, Xu Zewei , has been charged with nine counts of wire fra...

US Announces Arresting Chinese Hacker Linked to HAFNIUM Group

A Chinese state-sponsored hacker, Xu Zewei, 33, has been arrested for his alleged role in the widespread HAFNIUM cyber attacks and theft of COVID-19 research. Learn about the charges and China's Ministry of State Security involvement...

Detecting and preventing LSASS credential dumping attacks

Obtaining user operating system OS credentials from a targeted device is among threat actors’ primary goals when launching attacks because these credentials serve as a gateway to various objectives they can achieve in their target organization’s environment, such as lateral movement. One techniqu...

WARNING: New Unpatched Microsoft Exchange Zero-Day Under Active Exploitation

Security researchers are warning of previously undisclosed flaws in fully patched Microsoft Exchange servers being exploited by malicious actors in real-world attacks to achieve remote code execution on affected systems. The advisory comes from Vietnamese cybersecurity company GTSC, which...

Defending Against Scheduled Task Attacks in Windows Environments

Scheduling tasks is one of the most popular attack techniques used by threat actors to establish persistence on a victim’s machine. The Qualys Research Team investigated different ways that attackers could use to conceal scheduled tasks. In this blog, we describe three new techniques to hide and...

Millions of Java Apps Remain Vulnerable to Log4Shell

Four months after the discovery of the zero-day Log4Shell critical flaw, millions of Java applications still remain vulnerable to compromise, researchers have found. Rezilion expected that due to the “massive amount of media coverage” the bug unsurprisingly received, the majority of applications...

Microsoft Exposes Evasive Chinese Tarrask Malware Attacking Windows Computers

The Chinese-backed Hafnium hacking group has been linked to a piece of a new malware that's used to maintain persistence on compromised Windows environments. The threat actor is said to have targeted entities in the telecommunication, internet service provider and data services sectors from Augus...

Tarrask malware uses scheduled tasks for defense evasion

As Microsoft continues to track the high-priority state-sponsored threat actor HAFNIUM, new activity has been uncovered that leverages unpatched zero-day vulnerabilities as initial vectors. The Microsoft Detection and Response Team DART in collaboration with the Microsoft Threat Intelligence Cent...

Tarrask malware uses scheduled tasks for defense evasion

As Microsoft continues to track the high-priority state-sponsored threat actor HAFNIUM, new activity has been uncovered that leverages unpatched zero-day vulnerabilities as initial vectors. The Microsoft Detection and Response Team DART in collaboration with the Microsoft Threat Intelligence Cent...

Hackers Begin Exploiting Second Log4j Vulnerability as a Third Flaw Emerges

Web infrastructure company Cloudflare on Wednesday revealed that threat actors are actively attempting to exploit a second bug disclosed in the widely used Log4j logging utility, making it imperative that customers move quickly to install the latest version as a barrage of attacks continues to...

Relentless Log4j Attacks Include State Actors, Possible Worm

Call it a “logjam” of threats: Attackers including nation-state actors have already targeted half of all corporate global networks in security companies’ telemetry using at least 70 distinct malware families — and the fallout from the Log4j vulnerability is just beginning. Researchers manning...

Microsoft Issues Patches for Actively Exploited Excel, Exchange Server 0-Day Bugs

Microsoft has released security updates as part of its monthly Patch Tuesday release cycle to address 55 vulnerabilities across Windows, Azure, Visual Studio, Windows Hyper-V, and Office, including fixes for two actively exploited zero-day flaws in Excel and Exchange Server that could be abused t...

How to Reduce Exchange Server Downtime in Case of a Disaster?

Exchange Server downtime may occur at any point in time due to several reasons, such as malware attack, server crash, database corruption, and hardware or software-related issues/incompatibility. However, downtime can impact productivity and lead to data loss that can have severe implications on...

US, EU, UK, NATO blame china for “reckless” Exchange attacks

Do you remember back when the latest urgent update was a vulnerability in Microsoft Exchange? How is that only four months ago? The trigger for the urgent advice in March was the fact that Microsoft detected multiple zero-day exploits being used to attack on-premises versions of Microsoft Exchang...

US and Global Allies Accuse China of Massive Microsoft Exchange Attack

The U.S. government and its key allies, including the European Union, the U.K., and NATO, formally attributed the massive cyberattack against Microsoft Exchange email servers to state-sponsored hacking crews working affiliated with the People's Republic of China's Ministry of State Security MSS. ...

APT trends report Q1 2021

For four years, the Global Research and Analysis Team GReAT at Kaspersky has been publishing quarterly summaries of advanced persistent threat APT activity. The summaries are based on our threat intelligence research and provide a representative snapshot of what we have published and discussed in...