CVE-2026-8247: An Out-of-bounds Write vulnerability in WatchGuard Fireware OS may allow an unauthenticated attacker on the same local network segment to execute arbitrary…

PriorityP357high8.8CVSS 3.1

AVAACLPRNUINSUCHIHAH

EPSS

0.27%

19.2th percentile

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.

Affected

11 ranges

Vendor	Product	Version range	Fixed in
watchguard	fireware	—	—
watchguard	fireware	—	—
watchguard	fireware	>= 11.0.0 < 11.12.4	11.12.4
watchguard	fireware	>= 12.0 < 12.12.1	12.12.1
watchguard	fireware	>= 12.5 < 12.5.19	12.5.19
watchguard	fireware	>= 2025.1 < 2026.2.1	2026.2.1
watchguard	fireware_os	>= 11.0 < *	*
watchguard	fireware_os	>= 12.0 < 12.12.1	12.12.1
watchguard	fireware_os	>= 12.0 < 12.11.9	12.11.9
watchguard	fireware_os	>= 12.0 < 12.5.19	12.5.19
watchguard	fireware_os	>= 2025.1 < 2026.2.1	2026.2.1

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv4.07.7HIGHCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/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

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