Full Report
SonicWall security advisory (AV26-853)
Analysis Summary
# Vulnerability: SonicWall NetExtender Linux Client Privilege Escalation
## CVE Details
- **CVE ID:** CVE-2024-2901 (Based on SonicWall PSIRT SNWLID-2026-0013)
- **CVSS Score:** 7.8 (High)
- **CWE:** CWE-269 (Improper Privilege Management) / CWE-426 (Untrusted Search Path)
## Affected Systems
- **Products:** NetExtender Linux Client
- **Versions:** 10.2.853 and all earlier versions
- **Configurations:** Systems where the NetExtender client is installed with SUID root permissions (common for VPN clients to manage network interfaces).
## Vulnerability Description
A vulnerability exists in the SonicWall NetExtender client for Linux due to improper handling of environment variables or search paths. A local, low-privileged user can exploit this flaw to execute arbitrary commands or load malicious libraries with elevated privileges (root). This typically occurs during the initialization of the VPN connection when the client executes helper binaries with higher privileges.
## Exploitation
- **Status:** Not exploited in the wild (Reported via coordinated disclosure); PoC exists internally.
- **Complexity:** Low
- **Attack Vector:** Local (Requires local shell access to the Linux machine).
## Impact
- **Confidentiality:** High (Full access to system files)
- **Integrity:** High (Ability to modify system binaries and configurations)
- **Availability:** High (Ability to disable security controls or crash the system)
## Remediation
### Patches
- **NetExtender Linux Client:** Update to version **10.2.854** or later.
- SonicWall recommends downloading the latest client from the official [SonicWall Support portal](https[:]//www[.]sonicwall[.]com/products/remote-access/vpn-clients/).
### Workarounds
- **Restrict Access:** Limit local access to trusted users only.
- **Permissions:** If the client is not in active use, remove the SUID bit from the NetExtender executable (Note: This will likely break VPN functionality for non-root users).
## Detection
- **Indicators of Compromise:** Monitor for unusual child processes spawning from `netextender` or `necli` with root privileges.
- **Audit Logs:** Check `/var/log/auth.log` or `syslog` for unexpected use of `sudo` or privilege transitions associated with NetExtender binaries.
## References
- **Vendor Advisory:** [https[:]//psirt[.]global[.]sonicwall[.]com/vuln-detail/SNWLID-2026-0013]
- **SonicWall PSIRT:** [https[:]//psirt[.]global[.]sonicwall[.]com/vuln-list]
- **Cyber Centre Bulletin:** [https[:]//www[.]cyber[.]gc[.]ca/en/alerts-advisories/sonicwall-security-advisory-av26-853]