CVE-2026-13086#

Fireware OS Stack-Based Buffer Overflow in Mobile Security epm Endpoint

Critical 9.3 CVSS v4.0 › Published 2026-08-27Updated 2026-09-03

Summary #

A stack-based buffer overflow in the epm (Endpoint Protection Manager) service used by the deprecated Mobile Security feature in WatchGuard Fireware OS allows an unauthenticated remote attacker to execute arbitrary code.

Product status #

Product	Affected	Not affected
Fireware OS
Default	>= 2026.3, < 2026.3.1, >= 2025.0, < 2026.2.2, >= 12.0, < 12.12.2	>= 2026.3.1, >= 2026.2.2, >= 12.12.2
T15/T35	>= 12.0, < 12.5.20	>= 12.5.20

Weakness Type and Impact #

CWECWE-121Stack-based Buffer Overflow
CWECWE-787Out-of-bounds Write
CWECWE-798Use of Hard-coded Credentials
CAPECCAPEC-46Overflow Variables and Tags
CAPECCAPEC-100Overflow Buffers

Exploitation Status #

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

Solution #

Fireware OS 2026.3.1, Fireware OS 2026.2.2, Fireware OS 12.12.2, Fireware OS 12.5.20

References #

Credits #

Mat Powell of TrendAI Zero Day Initiativefinder