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.
Advisories
Source ID Title
EUVD EUVD EUVD-2022-51510 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.
Fixes

Solution

Netskope has patched the vulnerability and released a binary with a fix. Customers are recommended to upgrade their Netskope clients to v100 or later. Netskope download Instructions – Download Netskope Client and Scripts – Netskope Support https://support.netskope.com/s/article/Download-Netskope-Client-and-Scripts


Workaround

Netskope recommends using hardening guidelines listed here - – https://docs.netskope.com/en/netskope-client-hardening.html https://docs.netskope.com/en/netskope-client-hardening.html  

History

Thu, 12 Dec 2024 17:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Netskope

Published:

Updated: 2024-12-12T17:05:07.261Z

Reserved: 2022-11-28T12:19:11.243Z

Link: CVE-2022-4149

cve-icon Vulnrichment

Updated: 2024-08-03T01:27:54.588Z

cve-icon NVD

Status : Modified

Published: 2023-06-15T07:15:08.710

Modified: 2024-11-21T07:34:40.340

Link: CVE-2022-4149

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.