Critical severity · published Aug 27, 2026
CVE-2026-13086
Fireware OS Stack-Based Buffer Overflow in Mobile Security epm Endpoint
9.3
CVSS
0.7%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
Fireware OS · WatchGuard
2025.0 before 2026.2.2; 12.0 before 12.12.2; 2026.3 before 2026.3.1; 12.0 before 12.5.20 · source: vendor
In the news
VulnerabilityHigh
ZDI-26-632: WatchGuard FireWare OS epm connect Stack-based Buffer Overflow Remote Code Execution Vulnerability
This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of WatchGuard FireWare OS. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 8.8. The following CVEs are assigned: CVE-2026-13086.
Sep 9, 2026·Zero Day Initiative
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-13086
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-13086
psirt.watchguard.com
https://psirt.watchguard.com/CVE-2026-13086
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