The Netskope client service (prior to R96) on Windows runs as NT AUTHORITY\SYSTEM which writes log files to a writable directory (C:\Users\Public\netSkope) for a standard user. The files are created and written with a SYSTEM account except one file (logplaceholder) which inherits permission giving all users full access control list. Netskope client restricts access to this file by allowing only read permissions as a standard user. Whenever the Netskope client service restarts, it deletes the logplaceholder and recreates, creating a race condition, which can be exploited by a malicious local user to create the file and set ACL permissions on the file. Once the file is created by a malicious user with proper ACL permissions, all files within C:\Users\Public\netSkope\ becomes modifiable by the unprivileged user. By using Windows pseudo-symlink, these files can be pointed to other places in the system and thus malicious users will be able to elevate privileges.
2023-06-15T07:15:08.710
2024-11-21T07:34:40.340
Modified
CVSSv3.1: 7.0 (HIGH)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | netskope | netskope | < 100 | Yes |
| Operating System | microsoft | windows | - | No |