Vulnerability · Published Sep 29, 2026 · Assigned by WatchGuard

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

High 7.1

In plain English

A high-severity path traversal in Fireware OS from WatchGuard. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities).

Severity (CVSS 4.0)7.1High

Exploit odds (30 days)0.3%top 77.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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.

Affected products (as reported)

Vendor	Product	Versions
WatchGuard	Fireware OS	2026.0 – before 2026.3.22025.0 – before 2026.2.312.0 – before 12.12.3
WatchGuard	Fireware OS	12.0 – before 12.5.21

Weakness: CWE-22, CWE-476, CWE-862 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N

References

https://psirt.watchguard.com/CVE-2026-86136 vendor-advisory