CVE-2026-86104#

Fireware OS Resource Exhaustion in Login Process Allows Denial of Service

High 8.7 CVSS v4.0 › Published 2026-09-29Updated 2026-09-29

Summary #

An uncontrolled resource consumption vulnerability in the Fireware OS login process (wgagent) allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted request.

Product status #

Product	Affected	Not affected
Fireware OS
Default	>= 2026.3, < 2026.3.2, >= 2025.0, < 2026.2.3, >= 12.0, < 12.12.3	>= 2026.3.2, >= 2026.2.3, >= 12.12.3
T15/T35	>= 12.0, < 12.5.21	>= 12.5.21

Weakness Type and Impact #

CWECWE-400Uncontrolled Resource Consumption
CWECWE-409Improper Handling of Highly Compressed Data (Data Amplification)
CWECWE-770Allocation of Resources Without Limits or Throttling
CAPECCAPEC-130Excessive Allocation
CAPECCAPEC-197Exponential Data Expansion

Exploitation Status #

WatchGuard is not aware of any exploitation of this vulnerability in the wild.

Solution #

Fireware OS 2026.3.2, Fireware OS 2026.2.3, Fireware OS 12.12.3, Fireware OS 12.5.21

References #

Credits #

WatchGuard AI Security Researchfinder
Laurent GAFFIE , secorizon.comfinder