#VU67032 Improper Verification of Source of a Communication Channel in FortiOS - CVE-2022-27491
Published: September 6, 2022
Vulnerability identifier: #VU67032
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2022-27491
CWE-ID: CWE-940
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
FortiOS
FortiOS
Software vendor:
Fortinet, Inc
Fortinet, Inc
Description
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to improper verification of the communication channel source when handling TCP connections. A remote attacker can force the device to send "blocked page" HTML data to an arbitrary victim via specially crafted TCP requests and perform TCP Middlebox Reflection attack.
Successful exploitation of the vulnerability requires that at least one firewall policy has inspection mode set to flow-based (default) and at least one Security Profile is enabled (e.g. Web Filter, AntiVirus, IPS, DLP, Application Control, SSL, File filter).
Remediation
Install updates from vendor's website.