Denial of service in FortiAnalyzer OpenSSL library

1) Infinite loop

EUVDB-ID: #VU61391

Risk: Medium

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:U/RC:C]

CVE-ID: CVE-2022-0778

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop within the BN_mod_sqrt() function when processing an ASN.1 certificate that contains elliptic curve public keys in compressed form or explicit elliptic curve parameters with a base point encoded in compressed form. A remote attacker can supply a specially crafted certificate to the TLS server or client, consume all available system resources and cause denial of service conditions.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

FortiAnalyzer: 6.2.0 - 7.0.3

External links

http://fortiguard.fortinet.com/psirt/FG-IR-22-059

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.