CVE-2026-86136 Fireware OS Missing Authorization in wgagent Management API Allows Denial of Service - Variant A

What is CVE-2026-86136?

CVE-2026-86136 is a high-severity missing authorization vulnerability in Watchguard Fireware, published on 29 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

A missing authorization vulnerability in the wgagent management daemon's session initialization function allows an authenticated, low-privileged user (including a read-only or guest administrator account) to crash the wgagent process and read arbitrary files accessible to the daemon by submitting a specially crafted management API request.

Weakness: CWE-862, CWE-476, CWE-22

Which versions are affected by CVE-2026-86136?

It affects 1 product.

Products include Watchguard Fireware.

How do I fix CVE-2026-86136?

No fix has been published for CVE-2026-86136 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-86136 being exploited?

There is no known exploitation of CVE-2026-86136 in the wild and no public exploit code.

Other vulnerabilities in Watchguard Fireware

• CVE-2022-26318 WatchGuard Firebox and XTM Appliances Arbitrary Code Execution Exploited Critical 9.8
• CVE-2025-14733 WatchGuard Firebox Out of Bounds Write Exploited Critical 9.3
• CVE-2025-9242 WatchGuard Firebox Out-of-Bounds Write Exploited Critical 9.3
• CVE-2022-23176 WatchGuard Firebox and XTM Privilege Escalation Exploited High 8.8
• CVE-2022-31789 Integer overflow in n/a Critical 9.8

All Watchguard Fireware vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-34hp-73hm-xf3h.