WatchGuard TechnologiesCVE-2026-81851

WatchGuard Technologies Fireware OS: heap buffer overflow

Medium6.9CVE-2026-81851 · Published Aug 28, 2026

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.

WatchGuard Technologies advisory

Affected versions

Package	Affected	Fixed in
Fireware OS Product	>= 2025.0, < 2026.2.1	2026.2.1
	>= 12.0, < 12.12.1	12.12.1
	>= 12.0, < 12.11.9	12.11.9
	>= 12.0, < 12.5.18	12.5.18

Details and references

CVSS 4.0: 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/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
Severity from: the vendor (its own CVE record or advisory)
Weakness: CWE-122, CWE-1284

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All WatchGuard Technologies

Date	Advisory	Severity	Fixed in
Aug 28	WatchGuard Technologies Dimension: SQL injection High8.6Aug 28 CVE-2026-786142.3.1	High8.6	2.3.1
Aug 28	WatchGuard Technologies Dimension: cross-site scripting Medium4.6Aug 28 CVE-2026-786152.3.1	Medium4.6	2.3.1
Aug 28	WatchGuard Technologies Dimension: cross-site scripting Medium4.8Aug 28 CVE-2026-786162.3.1	Medium4.8	2.3.1
Aug 28	WatchGuard Technologies Dimension: observable discrepancy Medium6.3Aug 28 CVE-2026-786172.3.1	Medium6.3	2.3.1
Aug 28	WatchGuard Technologies Dimension: improper access control Medium6.9Aug 28 CVE-2026-786182.3.1	Medium6.9	2.3.1
Aug 28	WatchGuard Technologies Dimension: server-side request forgery Medium5.3Aug 28 CVE-2026-784952.3.1	Medium5.3	2.3.1

Affected versions

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