Advisoriesby IbisWatchGuard TechnologiesCVE-2026-81851
WatchGuard Technologies Fireware OS: heap buffer overflow
Fix: upgrade to 2026.2.1 or later (4 fixed versions below)
A heap-based buffer overflow vulnerability in Fireware OS's iked process allows an authenticated administrator to crash the IKE daemon (iked), resulting in a denial of service, by saving a specially crafted configuration.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Fireware OS Product | >= 2025.0, < 2026.2.1 | 2026.2.1 |
| >= 12.0, < 12.12.1 | 12.12.1 | |
| >= 12.0, < 12.11.9 | 12.11.9 | |
| >= 12.0, < 12.5.18 | 12.5.18 |