Vulnerability · Published Aug 27, 2026 · Assigned by WatchGuard
CVE-2026-13086Fireware OS Stack-Based Buffer Overflow in Mobile Security epm Endpoint
Critical 9.3
In plain English
A critical-severity stack buffer overflow in Fireware OS from WatchGuard. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).
Severity (CVSS 4.0)9.3Critical
Exploit odds (30 days)0.7%top 48.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WatchGuard | Fireware OS | 2025.0 – before 2026.2.212.0 – before 12.12.22026.3 – before 2026.3.1 |
| WatchGuard | Fireware OS | 12.0 – before 12.5.20 |
Weakness: CWE-121, CWE-787, CWE-798 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
References
- https://psirt.watchguard.com/CVE-2026-13086 vendor-advisory