CVE-2026-13046: WatchGuard Fireware

High severity, CVSS 7.2. EPSS: 0.4% chance of exploitation in the next 30 days.

A deserialization of untrusted data vulnerability in WatchGuard Fireware OS's SAML single sign-on session handling (samld) allows an attacker who has already obtained the ability to write files on the appliance to execute arbitrary code in the context of the samld service by causing samld to load a maliciously crafted session file.

Affected products

• WatchGuard Fireware: from 12.0, before 12.11.10 (fixed in 12.11.10); from 12.12, before 12.12.3 (fixed in 12.12.3); from 2025.0, before 2026.2.3 (fixed in 2026.2.3); from 2026.3, before 2026.3.2 (fixed in 2026.3.2)

Published 2026-09-30. Last modified 2026-10-08.