CVE-2026-86131

Critical

Description

A code injection vulnerability in WatchGuard Fireware OS's BOVPN Over TLS client configuration handling allows an attacker who controls the remote VPN server to execute arbitrary commands as root on the connecting Firebox.

SeverityCritical

CVSS9.8

Exploit probability—

ProductWatchguard Fireware

PublishedSep 30, 2026

First seenSep 30, 2026

Weakness typeCWE-295CWE-295 CWE-829CWE-829 CWE-94Code injection

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-2026-86131

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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