Fireware OS Code Injection in BOVPN Over TLS Client Allows Remote Code Execution

published 2026-09-29 40 d ago modified 2026-10-06 33 d ago also EUVD-2026-89497

cvss: 9.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits: 0; none known

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.

Patch / fix

fixed in 1 links 1

WatchGuard Fireware OS 12.5.21, 12.12.3, 2026.2.3, 2026.3.2

psirt.watchguard.com/CVE-2026-86131 advisory

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: 38 d ago (2026-10-01)

Exploit prediction

0.47% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.2	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
CNA	4.0	9.2	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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

WatchGuard Fireware OS

Classification

Weakness

CWE-295 Improper Certificate Validation
CWE-829 Inclusion of Functionality from Untrusted Control Sphere
CWE-94 Improper Control of Generation of Code

References

psirt.watchguard.com /CVE-2026-86131
vendor-advisory, patch

Sources

CVE List CVE-2026-86131
NVD CVE-2026-86131

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary