Vulnerability · Published Aug 27, 2026 · Assigned by WatchGuard
CVE-2026-19318Fireware OS Pre-Authentication Stack Buffer Overflow in iked Allows Remote Code Execution
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 54% of all known vulnerabilities).
Severity (CVSS 4.0)9.3Critical
Exploit odds (30 days)0.7%top 46.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A stack-based buffer overflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to execute arbitrary code by sending specially crafted network traffic.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WatchGuard | Fireware OS | 2025.0 – before 2026.2.212.0 – before 12.12.2 |
| WatchGuard | Fireware OS | 12.0 – before 12.5.202026.3 – before 2026.3.1 |
Weakness: CWE-121, CWE-129, CWE-191 · 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-2026-19318 vendor-advisory