CVE-2026-78011

published 2026-08-28

CVE-2026-78011: An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS)…

Priority P3 57 high 8.7 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 E X CR X IR X AR X MAV X MAC X MAT X MPR X MUI X MVC X MVI X MVA X MSC X MSI X MSA X S X AU X R X V X RE X U X

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

4 ranges

Vendor	Product	Version range	Fixed in
watchguard	fireware_os	>= 12.0 < 12.12.2	12.12.2
watchguard	fireware_os	>= 12.0 < 12.5.20	12.5.20
watchguard	fireware_os	>= 2025.0 < 2026.2.2	2026.2.2
watchguard	fireware_os	>= 2026.3 < 2026.3.1	2026.3.1

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CWE-191 CWE-787