CVE-2026-13371#
WatchGuard Firebox Management Web UI Denial of Service via Unsafe Deserialization
Summary #
An authenticated administrator can trigger a denial-of-service condition in the Fireware Management Web UI by sending malformed or crafted data to the put_data endpoint, which performs unsafe deserialization of the attacker-supplied input.
Product status #
| Product | Affected | Not affected |
|---|---|---|
| Fireware OS | ||
| Default | >= 2025.1, < 2026.2.1, >= 12.0, < 12.12.1 | >= 2026.2.1, >= 12.12.1 |
| T15/T35 | >= 12.0, < 12.5.19 | >= 12.5.19 |
| EUCC | >= 12.0, < 12.11.9 | >= 12.11.9 |
Weakness Type and Impact #
Exploitation Status #
WatchGuard is not aware of any exploitation of this vulnerability in the wild.
Solution #
Fireware OS 2026.2.1, Fireware OS 12.12.1, Fireware OS 12.11.9, Fireware OS 12.5.19
References #
Credits #
- Cody Sixteenfinder