What’s Vulnerable › Vulnerabilities
CVE-2026-86104: Fireware OS Resource Exhaustion in Login Process Allows Denial of Service
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-30 · updated 2026-10-06
- Weakness: CWE-400
Description
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 products
- WatchGuard Fireware OS: from 12.0 before 12.5.21; from 12.12 before 12.12.3; from 2025.0 before 2026.2.3; from 2026.3 before 2026.3.2 — fixed in 12.12.3, 12.5.21, 2026.2.3, 2026.3.2
How to fix
Upgrade to a fixed version: WatchGuard Fireware OS 12.12.3, 12.5.21, 2026.2.3, 2026.3.2. Check the vendor advisory for mitigations.
References
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