CVE-2021-43204: Fortinet FortiClient

Medium severity, CVSS 4.4. EPSS: 0.4% chance of exploitation in the next 30 days.

A improper control of a resource through its lifetime in Fortinet FortiClientWindows version 6.4.1 and 6.4.0, version 6.2.9 and below, version 6.0.10 and below allows attacker to cause a complete denial of service of its components via changes of directory access permissions.

Affected products

• Fortinet FortiClient: from 5.0.0, up to and including 5.0.11; from 5.4.0, up to and including 5.4.5; from 5.6.0, up to and including 5.6.6; from 6.0.0, up to and including 6.0.10; from 6.2.0, up to and including 6.2.9; version 4.0.1 only; …

Published 2021-12-09. Last modified 2026-06-17.