WatchGuard security advisory (AV26-981)

Serial number: AV26-981
Date: October 1, 2026

As of September 30, 2026, WatchGuard is affected by a vulnerability in the following product:

• Fireware OS
  • Prior to 12.12.3
  • Prior to 12.5.21
  • Prior to 2026.2.3
  • Prior to 2026.3.2

The Cyber Centre encourages users and administrators to review the provided web links and apply any necessary updates as they become available.

• CVE-2026-86134 — Fireware OS Pre-Authentication NULL Pointer Dereference Allows Remote Denial of Service
• WatchGuard Security Advisories