CVE-2025-13940

WatchGuard Firebox Boot Time System Integrity Check Bypass

MEDIUM

5.5

CVSS Score

Published: December 4, 2025 at 09:47 PM UTC

Updated: September 25, 2026 at 11:27 PM UTC

32 products affected across 1 vendorFirewareFirebox T55Firebox M4800

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Severity

MEDIUM5.5

Exploit prediction

EPSS 0.1%

SSVC

No known exploit

Description

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.This issue affects Fireware OS: from 12.8.1 through 12.11.4, from 2025.1 through 2025.1.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Fireware · WatchGuard

95%

12.8.1 ≤ v < 12.11.52025.1 ≤ v < 2025.1.312.8.1 2025.1

Affected range stops below 12.11.5, so it looks safe — our inference, not a vendor statement

Affected range stops below 2025.1.3, so it looks safe — our inference, not a vendor statement

watchguard-firebox-m270 (environment) · watchguard-firebox-m290 (environment) · watchguard-firebox-m370 (environment) · watchguard-firebox-m390 (environment) · watchguard-firebox-m440 (environment) · watchguard-firebox-m4600 (environment) · watchguard-firebox-m470 (environment) · watchguard-firebox-m4800 (environment) · watchguard-firebox-m5600 (environment) · watchguard-firebox-m570 (environment) · watchguard-firebox-m5800 (environment) · watchguard-firebox-m590 (environment) · watchguard-firebox-m670 (environment) · watchguard-firebox-m690 (environment) · watchguard-firebox-nv5 (environment) · watchguard-firebox-t115-w (environment) · watchguard-firebox-t125 (environment) · watchguard-firebox-t125-w (environment) · watchguard-firebox-t145 (environment) · watchguard-firebox-t145-w (environment) · watchguard-firebox-t185 (environment) · watchguard-firebox-t20 (environment) · watchguard-firebox-t25 (environment) · watchguard-firebox-t40 (environment) · watchguard-firebox-t45 (environment) · watchguard-firebox-t55 (environment) · watchguard-firebox-t70 (environment) · watchguard-firebox-t80 (environment) · watchguard-firebox-t85 (environment) · watchguard-fireboxcloud (environment) · watchguard-fireboxv (environment)

Firebox M270 · WatchGuarddevice

80%

All versions

Firebox M290 · WatchGuarddevice

80%

All versions

Firebox M370 · WatchGuarddevice

80%

All versions

Firebox M390 · WatchGuarddevice

80%

All versions