CVE-2026-103594
Critical
Description
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing allows a remote attacker that has man-in-the-middle TLS-decrypted access between the Firebox and WatchGuard Cloud to create a Denial of Service condition and potentially execute arbitrary code by tampering with a FireCloud Gateway configuration payload.
SeverityCritical
CVSS9.5
Exploit probability—
ProductFireware OS
PublishedOct 27, 2026
First seenOct 27, 2026
How to fix
Update
- WatchGuard Fireware OS2026.4, 12.12.4 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| WatchGuard Fireware OS | 2026.2 ≤ v < 2026.4, 12.12 ≤ v < 12.12.4 | 2026.4, 12.12.4 |
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