Firebox and Fireware OS

CVE-2025-13940: WatchGuard Firebox Boot Time System Integrity Check Bypass

An Expected Behavior Violation [CWE-440] vulnerability in WatchGuard Fireware OS may allow an attacker to bypass the Fireware OS boot time system integrity check and prevent the Firebox from shutting down in the event of a system integrity check failure.

Published

ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityMEDIUMCVSS 4.0 6.7
EPSS0.13%Chance of exploitation in 30 days
Public exploitNot tracked
FixAvailable

Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.

Affected and fixed versions

Product / branchFixed in
Fireware OS 2025.12025.1.3 or later
Fireware OS 12.812.11.5 or later

Always confirm against the vendor advisory, which lists every fixed hotfix.

What it is

An Expected Behavior Violation [CWE-440] vulnerability in WatchGuard Fireware OS may allow an attacker to bypass the Fireware OS boot time system integrity check and prevent the Firebox from shutting down in the event of a system integrity check failure. The on-demand system integrity check in the Fireware Web UI will correctly show a failed system integrity check message in the event of a failure.

Exploitation

WatchGuard is not aware of any exploitation of this vulnerability in the wild.

Sources

KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.

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