CVE-2026-8247
High
Description
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.
SeverityHigh
CVSS8.8
Exploit probability—
ProductWatchguard Fireware
PublishedJul 3, 2026
First seenJul 3, 2026
Weakness typeCWE-120CWE-120
How to fix
Update
- watchguard fireware11.12.4, 12.5.19, 2026.2.1, 12.12.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| watchguard fireware | 11.0.0 ≤ v < 11.12.4, 11.12.4, 12.5 ≤ v < 12.5.19, 2025.1 ≤ v < 2026.2.1, 12.0 ≤ v < 12.12.1 | 11.12.4, 12.5.19, 2026.2.1, 12.12.1 |
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