What’s Vulnerable › Vulnerabilities
CVE-2024-20331: Cisco Adaptive Security Appliance and Firepower Threat Defense Software VPN Authentication DoS Vulnerability
- Severity: medium (CVSS 5.9 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.7% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2024-10-23 · updated 2026-08-11
- Weakness: CWE-330
Description
A vulnerability in the session authentication functionality of the Remote Access SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to prevent users from authenticating. This vulnerability is due to insufficient entropy in the authentication process. An attacker could exploit this vulnerability by determining the handle of an authenticating user and using it to terminate their authentication session. A successful exploit could allow the attacker to force a user to restart the authentication process, preventing a legitimate user from establishing remote access VPN sessions.
Affected products
- Cisco ASA Software: 9.8.1, 9.8.1.5, 9.8.1.7, 9.8.2, 9.8.2.8, 9.8.2.14 (+182)
- Cisco Firepower Threat Defense Software: 6.2.3, 6.2.3.1, 6.2.3.2, 6.2.3.3, 6.2.3.4, 6.2.3.5 (+78)
References
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-vpn-nyH3fhp
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-xss-M446vbEO
- https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75300
Get alerted when CVE-2024-20331 or the next vulnerability affects your stack