CVE-2026-81851

Medium

Description

A heap-based buffer overflow vulnerability in Fireware OS's iked process allows an authenticated administrator to crash the IKE daemon (iked), resulting in a denial of service, by saving a specially crafted configuration.

SeverityMedium

CVSS6.9

Exploit probability—

ProductFireware OS

PublishedAug 28, 2026

First seenAug 28, 2026

Weakness typeCWE-122CWE-122 CWE-1284CWE-1284

How to fix

Update

WatchGuard Fireware OS2026.2.1, 12.12.1, 12.11.9, 12.5.18 or later

Vendor advisories

psirt.watchguard.com/CVE-2026-81851

Affected products

Product	Affected versions	Fixed in
WatchGuard Fireware OS	2025.0 ≤ v < 2026.2.1, 12.0 ≤ v < 12.12.1, 12.0 ≤ v < 12.11.9, 12.0 ≤ v < 12.5.18	2026.2.1, 12.12.1, 12.11.9, 12.5.18

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