Vulnerability · Published Sep 29, 2026 · Assigned by WatchGuard
CVE-2026-86131Fireware OS Code Injection in BOVPN Over TLS Client Allows Remote Code Execution
Critical 9.2
In plain English
A critical-severity improper certificate validation 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 0.5% (higher than 41% of all known vulnerabilities).
Severity (CVSS 4.0)9.2Critical
Exploit odds (30 days)0.5%top 59.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A code injection vulnerability in WatchGuard Fireware OS's BOVPN Over TLS client configuration handling allows an attacker who controls the remote VPN server to execute arbitrary commands as root on the connecting Firebox.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WatchGuard | Fireware OS | 2026.3 – 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-295, CWE-829, CWE-94 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
References
- https://psirt.watchguard.com/CVE-2026-86131 vendor-advisory