CVE-2026-18105

Medium

Description

An uncontrolled resource consumption vulnerability in Fireware OS's diagnostic tasks feature allows a low-privileged, authenticated user to cause a denial of service of the system's diagnostic tools by repeatedly starting and aborting a specially crafted diagnostic task through the web UI.

SeverityMedium

CVSS6.5

Exploit probability—

ProductWatchguard Fireware

PublishedSep 30, 2026

First seenSep 30, 2026

Weakness typeCWE-400Uncontrolled resource consumption CWE-770Allocation of resources without limits

How to fix

Update

watchguard fireware12.5.21, 12.12.3, 2026.2.3, 2026.3.2 or later

Vendor advisories

psirt.watchguard.com/CVE-2026-18105

Affected products

Product	Affected versions	Fixed in
watchguard fireware	12.0 ≤ v < 12.5.21, 12.12 ≤ v < 12.12.3, 2025.0 ≤ v < 2026.2.3, 2026.3 ≤ v < 2026.3.2	12.5.21, 12.12.3, 2026.2.3, 2026.3.2

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