RADIUS authentication bypass in FortiOS SSH component

1) Improper Authentication

EUVDB-ID: #VU69939

Risk: High

CVSSv4.0: 7.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2022-35843

CWE-ID: CWE-287 - Improper Authentication

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error in FortiOS SSH login component when processing authentication requests if RADIUS authentication is used. A remote attacker can bypass authentication process and login into the device via sending specially crafted Access-Challenge response from the Radius server.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

FortiOS: 6.4.0 - 7.2.1

CPE2.3

• cpe:2.3:o:fortinet:fortios:6.4.0:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.1:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.3:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.4:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.5:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.6:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.7:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.8:*:*:*:*:*:*:*
• cpe:2.3:o:fortinet:fortios:6.4.9:*:*:*:*:*:*:*

External links

https://fortiguard.com/psirt/FG-IR-22-255

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.