WatchGuard Fireware OS Affected by 15 Vulnerabilities Including Critical CVE-2026-86131
WatchGuard Technologies has disclosed 15 vulnerabilities affecting Fireware OS, the operating system used in its UTM appliances. The company released multiple security advisories on September 29–30, 2026.
Although the exact impact depends on each environment, the flaws collectively enable code execution, authorization bypass, unauthorized file access, and denial-of-service conditions. At the time of disclosure, WatchGuard stated that no exploitation in the wild had been confirmed.
Critical vulnerability in BOVPN Over TLS
The highest-rated issue, tracked as CVE-2026-86131, carries a CVSS v4.0 base score of 9.2 and a Critical severity rating. The flaw resides in the client-configuration processing logic of the BOVPN Over TLS feature. An attacker who can control the destination VPN server can inject code that results in arbitrary command execution with root privileges on the connecting Firebox appliance.
The remaining 14 vulnerabilities are documented in separate advisories and affect various subsystems of Fireware OS. They are identified by the following CVE numbers:
- CVE-2026-86134
- CVE-2026-86104
- CVE-2026-81433
- CVE-2026-18145
- CVE-2026-86132
- CVE-2026-86133
- CVE-2026-13224
- CVE-2026-86128
- CVE-2026-13046
- CVE-2026-86101
- CVE-2026-86136
- CVE-2026-90441
- CVE-2026-18105
- CVE-2026-86105
Administrators are advised to review the official WatchGuard advisories and apply the corresponding patches as soon as possible.
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