Vulnerability · Published Aug 27, 2026 · Assigned by WatchGuard
CVE-2026-19314Fireware OS Integer Underflow in iked Allows Unauthenticated Denial of Service (DoS)
High 8.7
In plain English
A high-severity out-of-bounds write 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 0.5% (higher than 46% of all known vulnerabilities).
Severity (CVSS 4.0)8.7High
Exploit odds (30 days)0.5%top 54.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS) condition in VPN processing by sending specially crafted network traffic.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WatchGuard | Fireware OS | 2025.0 – before 2026.2.212.0 – before 12.12.22026.3 – before 2026.3.1 |
| WatchGuard | Fireware OS | 12.0 – before 12.5.20 |
Weakness: CWE-191, CWE-787 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References
- https://psirt.watchguard.com/CVE-2026-19314 vendor-advisory