FreeBSD vulnerability

When a process calls execve(2) to execute a setuid or setgid image, hwpmc(4) is supposed to detach PMCs owned by unprivileged processes. An inverted check meant that this scenario was not handled properly. An unprivileged local user who has attached PMCs to a process can continue monitoring it after the process executes a setuid or setgid binary, contrary to the intended policy.

Published 26 Aug 2026Updated 24 Sep 20261 sources
CVSS 7.8

What happened

When a process calls execve(2) to execute a setuid or setgid image, hwpmc(4) is supposed to detach PMCs owned by unprivileged processes. An inverted check meant that this scenario was not handled properly. An unprivileged local user who has attached PMCs to a process can continue monitoring it after the process executes a setuid or setgid binary, contrary to the intended policy.

Affected versions

FreeBSD: 15.1-RELEASE through before p3 (release); 15.0-RELEASE through before p13 (release); 14.4-RELEASE through before p9 (release) 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.