CVE-2026-104381 PUBLISHED

Fireware OS Missing Authentication in FireCluster State Sync Allows BOVPN Tunnel Denial of Service

Assigner: WatchGuard
Reserved: 01.10.2026 Published: 27.10.2026 Updated: 27.10.2026

A missing authentication vulnerability in Fireware OS's FireCluster state synchronization feature allows an unauthenticated attacker positioned on the cluster synchronization network segment to force premature VPN tunnel termination by sending crafted cluster synchronization traffic.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
CVSS Score: 6

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Adjacent	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	Low	Integrity	None
Attack Requirements	Present	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	WatchGuard
Product	Fireware OS
Versions	Default: unaffected affected from 2025.1 to 2026.4 (excl.) affected from 12.0 to 12.12.4 (excl.)

Vendor	WatchGuard
Product	Fireware OS
Versions	Default: unaffected affected from 12.0 to 12.5.22 (excl.)

Affected Configurations

This vulnerability affects Firebox appliances deployed as a Firecluster and configured with at least one BOVPN tunnel.

Exploits

WatchGuard is not aware of any exploitation of this vulnerability in the wild.

Solutions

Fireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22

Credits

WatchGuard AI Security Research finder

References

https://psirt.watchguard.com/CVE-2026-104381

Problem Types

CWE-294 CWE
CWE-306 CWE
CWE-345 CWE