CVE-2026-103593

Fireware OS Stack Buffer Overflow in Logging Service Allows Remote Code Execution

State: Published
Severity: 9.1 Critical
Published: Oct 27, 2026
Updated: Oct 29, 2026
Reserved: Sep 30, 2026

Description

A stack-based buffer overflow vulnerability in the Fireware OS logging service allows a network-adjacent attacker who can impersonate or intercept traffic to the configured log server to execute arbitrary code with root privileges by presenting a specially crafted certificate.

Scores

CVSS	Score	Vector	Source
4.0	9.1 Critical	CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H	WatchGuard

Weaknesses

Affected Products

Product	Versions
Fireware OSWatchGuard	2025.1 to before 2026.4Affected 12.0 to before 12.12.4Affected
Fireware OSWatchGuard	12.0 to before 12.5.22Affected

References

https://psirt.watchguard.com/CVE-2026-103593vendor-advisory

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