CVE-2022-27491: Fortinet FortiOS

High severity, CVSS 7.5. EPSS: 1.4% chance of exploitation in the next 30 days.

A improper verification of source of a communication channel in Fortinet FortiOS with IPS engine version 7.201 through 7.214, 7.001 through 7.113, 6.001 through 6.121, 5.001 through 5.258 and before 4.086 allows a remote and unauthenticated attacker to trigger the sending of "blocked page" HTML data to an arbitrary victim via crafted TCP requests, potentially flooding the victim.

Affected products

• Fortinet FortiOS: from 6.0.0, up to and including 6.0.14; from 6.2.0, before 6.2.11 (fixed in 6.2.11); from 6.4.0, before 6.4.9 (fixed in 6.4.9); from 7.0.0, before 7.0.6 (fixed in 7.0.6); version 7.2.0 only

Published 2022-09-06. Last modified 2026-06-17.