CVE-2026-81851

Fireware OS Heap-Based Buffer Overflow in iked Allows Denial of Service

State: Published
Severity: 6.9 Medium
Published: Aug 27, 2026
Updated: Aug 28, 2026
Reserved: Aug 27, 2026

Description

A heap-based buffer overflow vulnerability in Fireware OS's iked process allows an authenticated administrator to crash the IKE daemon (iked), resulting in a denial of service, by saving a specially crafted configuration.

Scores

CVSS	Score	Vector	Source
4.0	6.9 Medium	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N	WatchGuard

Weaknesses

Affected Products

Product	Versions
Fireware OSWatchGuard	2025.0 to before 2026.2.1Affected 12.0 to before 12.12.1Affected
Fireware OSWatchGuard	12.0 to before 12.11.9Affected
Fireware OSWatchGuard	12.0 to before 12.5.18Affected

References

https://psirt.watchguard.com/CVE-2026-81851vendor-advisory

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