CVE-2024-20408: 
Cisco Adaptive Security Appliance (ASA) vulnerability analysis and mitigation

A vulnerability (CVE-2024-20408) has been identified in the Dynamic Access Policies (DAP) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software. This vulnerability was discovered during internal security testing by X.B. of the Cisco Advanced Security Initiatives Group (ASIG) and was publicly disclosed on October 23, 2024. The vulnerability affects systems running vulnerable releases of Cisco ASA Software or Cisco FTD Software where SSL VPN is enabled, at least one custom DAP is configured, and HostScan is enabled (Cisco Advisory).

The vulnerability stems from improper validation of data in HTTPS POST requests. It has been assigned a CVSS Base Score of 7.7 (High) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H. The vulnerability is classified under CWE-1287 (Improper Validation of Specified Type of Input) (Cisco Advisory, NVD).

A successful exploitation of this vulnerability could allow an attacker to cause the affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The impact is particularly significant as it affects the device's ability to process network traffic and maintain VPN connections (Cisco Advisory).

Cisco has released software updates that address this vulnerability. There are no workarounds available that address this vulnerability. Users are advised to upgrade to the latest software version. The specific version required depends on the product deployment. Customers can use the Cisco Software Checker to identify the appropriate update for their installation (Cisco Advisory).