CVE-2026-86104: Fireware OS Resource Exhaustion in Login Process Allows Denial of Service

Published Sep 29, 2026

Updated

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.

Affected Software

1 affected component

WatchGuard Fireware OS

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade Fireware OS to a version that resolves this vulnerability.
Fixed in 2026.3.2
Upgrade
Upgrade Fireware OS to a version that resolves this vulnerability.
Fixed in 2026.2.3
Upgrade
Upgrade Fireware OS to a version that resolves this vulnerability.
Fixed in 12.12.3
Upgrade
Upgrade Fireware OS to a version that resolves this vulnerability.
Fixed in 12.5.21

Event History

Sep 29, 2026

CVE Published

via MITRE·11:05 PM

Data Sourced

via MITRE·11:05 PM

RemedyDescriptionWeakness

Sep 30, 2026

Data Sourced

via NVD·12:16 AM

DescriptionSeverityWeakness

Frequently Asked Questions

Who can exploit this issue?

A remote, unauthenticated attacker can exploit the issue by sending a specially crafted request to the affected Fireware OS login process, wgagent.

What is the expected impact of a successful attack?

Successful exploitation can exhaust resources in the login process and cause a denial of service.