ClearOS vulnerability

ClearOS 7.9 contains an OS command injection vulnerability in the Log Viewer component that allows authenticated attackers to execute arbitrary commands by submitting unsanitized input through the filter parameter, which is interpolated directly into a shell command in File.php. Attackers can inject command substitution payloads into the filter parameter to execute arbitrary commands as the webconfig user, and due to extensive NOPASSWD sudo privileges granted to that user by default, immediately escalate to root.

Published 3 Aug 2026Updated 24 Sep 20263 sources
CVSS 8.6

What happened

ClearOS 7.9 contains an OS command injection vulnerability in the Log Viewer component that allows authenticated attackers to execute arbitrary commands by submitting unsanitized input through the filter parameter, which is interpolated directly into a shell command in File.php. Attackers can inject command substitution payloads into the filter parameter to execute arbitrary commands as the webconfig user, and due to extensive NOPASSWD sudo privileges granted to that user by default, immediately escalate to root.

Affected versions

ClearOS: 7.9 (custom) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.