CVE-2026-86128

published 2026-09-30

CVE-2026-86128: A NULL pointer dereference vulnerability in Fireware OS's NetFlow packet-processing feature allows a remote, unauthenticated attacker to cause a denial of…

Priority P3 43 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

A NULL pointer dereference vulnerability in Fireware OS's NetFlow packet-processing feature allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted IPv6 packet.

Affected

8 ranges

Vendor	Product	Version range	Fixed in
watchguard	fireware	>= 12.0 < 12.5.21	12.5.21
watchguard	fireware	>= 12.12 < 12.12.3	12.12.3
watchguard	fireware	>= 2025.0 < 2026.2.3	2026.2.3
watchguard	fireware	>= 2026.3 < 2026.3.2	2026.3.2
watchguard	fireware_os	>= 12.0 < 12.12.3	12.12.3
watchguard	fireware_os	>= 12.0 < 12.5.21	12.5.21
watchguard	fireware_os	>= 2025.0 < 2026.2.3	2026.2.3
watchguard	fireware_os	>= 2026.3 < 2026.3.2	2026.3.2

CVSS provenance

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd v4.0 8.2 HIGH CVSS:4.0/AV:N/AC:L/AT:P/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

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CWE-476