CVE-2026-4266EPSS p20.7%

CVE-2026-4266CVE-2026-4266

Description

An Insecure Deserialization vulnerability in WatchGuard Fireware OS allows an attacker that has obtained write access to the local filesystem through another vulnerability to execute arbitrary code in the context of the portald user. Note, this vulnerability does not affect Firebox platforms that do not support the Access Portal feature, including the T15 and T35.

Scoring

EPSS0.28% probability of exploitation · percentile 20.7% · 2026-08-11T12:00:17Z
Last modified2026-08-10
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.