CVE-2026-13371

Medium

Description

An authenticated administrator can trigger a denial-of-service condition in the Fireware Management Web UI by sending malformed or crafted data to the put_data endpoint, which performs unsafe deserialization of the attacker-supplied input.

SeverityMedium

CVSS4.9

Exploit probability—

ProductWatchguard Fireware

PublishedJul 3, 2026

First seenJul 3, 2026

Weakness typeCWE-502Deserialization of untrusted data

How to fix

Update

watchguard fireware2026.2.1, 12.5.19, 12.12.1 or later

Vendor advisories

psirt.watchguard.com/CVE-2026-13371
watchguard.com/wgrd-psirt/advisory/wgsa-2026-00014

Affected products

Product	Affected versions	Fixed in
watchguard fireware	2025.1 ≤ v < 2026.2.1, 12.5 ≤ v < 12.5.19, 12.0 ≤ v < 12.12.1	2026.2.1, 12.5.19, 12.12.1

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