A vulnerability in the remote access SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to bypass a configured multiple certificate authentication policy and connect using only a valid username and password. This vulnerability is due to improper error handling during remote access VPN authentication. An attacker could exploit this vulnerability by sending crafted requests during remote access VPN session establishment. A successful exploit could allow the attacker to bypass the configured multiple certificate authentication policy while retaining the privileges and permissions associated with the original connection profile.

References

• https://nvd.nist.gov/vuln/detail/CVE-2023-20247
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-multi-cert-dzA3h5PT