CVE-2026-3987 PUBLISHED

WatchGuard Firebox Arbitrary File Write vis Path Traversal in Fireware Web UI

Assigner: WatchGuard
Reserved: 11.03.2026 Published: 01.04.2026 Updated: 02.04.2026

A path traversal vulnerability in the Fireware OS Web UI on WatchGuard Firebox systems may allow a privileged authenticated remote attacker to execute arbitrary code in the context of an elevated system process.This issue affects Fireware OS 12.6.1 up to and including 12.11.8 and 2025.1 up to and including 2026.1.2.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.6

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	High
User Interaction	None

CVSS 4.0

Product Status

Vendor	WatchGuard
Product	Fireware OS
Versions	Default: unaffected affected from 12.6.1 to 12.11.8 (incl.) affected from 2025.1 to 2026.1.2 (incl.)

Exploits

WatchGuard is not aware of any exploitation of this issue in the wild.

Credits

btaol finder

References

https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2026-00009

Problem Types

CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE

Impacts

CAPEC-165 File Manipulation