CVE-2026-112709

Critical

Description

A heap-based buffer overflow vulnerability in the Fireware OS authentication service allows an attacker who controls or intercepts traffic to the configured Active Directory server to create a denial of service condition and potentially execute arbitrary code by returning a specially crafted response.

SeverityCritical

CVSS9.2

Exploit probability—

ProductFireware OS

PublishedOct 27, 2026

First seenOct 27, 2026

Weakness typeCWE-122CWE-122 CWE-131CWE-131 CWE-787Out-of-bounds write

How to fix

Update

WatchGuard Fireware OS2026.4, 12.12.4, 12.5.22 or later

Vendor advisories

psirt.watchguard.com/CVE-2026-112709

Affected products

Product	Affected versions	Fixed in
WatchGuard Fireware OS	2025.1 ≤ v < 2026.4, 12.0 ≤ v < 12.12.4, 12.0 ≤ v < 12.5.22	2026.4, 12.12.4, 12.5.22

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