Firebox and Fireware OS
CVE-2026-8247: WatchGuard Firebox admd Out of Bounds Write Vulnerability
An Out-of-bounds Write vulnerability in WatchGuard Fireware OS may allow an unauthenticated attacker on the same local network segment to execute arbitrary code.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Fireware OS (Default) 2025.1 | 2026.2.1 or later |
| Fireware OS (Default) 12.0 | 12.12.1 or later |
| Fireware OS (Default) 11.0 | * or later |
| Fireware OS (EUCC) 12.0 | 12.11.9 or later |
| Fireware OS (T15/T35) 12.0 | 12.5.19 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
An Out-of-bounds Write vulnerability in WatchGuard Fireware OS may allow an unauthenticated attacker on the same local network segment to execute arbitrary code.
This vulnerability affects Fireware OS 11.0 up to and including 11.12.4_Update1, 12.0 up to and including 12.12 and 2025.1 up to and including 2026.2.
Exploitation
WatchGuard is not aware of any exploitation of this vulnerability in the wild.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.