CVE-2021-36188: Fortinet FortiWeb

Medium severity, CVSS 6.1. EPSS: 0.7% chance of exploitation in the next 30 days.

A improper neutralization of input during web page generation ('cross-site scripting') in Fortinet FortiWeb version 6.4.1 and below, 6.3.15 and below allows attacker to execute unauthorized code or commands via crafted GET parameters in requests to login and error handlers

Affected products

• Fortinet FortiWeb: from 6.0.0, up to and including 6.2.5; from 6.3.0, before 6.3.16 (fixed in 6.3.16); from 6.4.0, before 6.4.2 (fixed in 6.4.2)

Published 2021-12-08. Last modified 2026-06-17.