This vulnerability affects all Cisco Secure Firewall ASA and FTD Software platforms. It stems from a lack of proper memory management for new incoming SSL/TLS connections in the VPN and management web servers. An unauthenticated remote attacker can exploit this by sending a large volume of new SSL/TLS connection requests, causing the device to run out of system memory or buffer blocks. This resource exhaustion leads to slowed or halted SSL VPN connection processing, resulting in a denial of service. Memory and buffers may be reclaimed slowly after attack traffic ceases, but a manual reload might be necessary to quickly restore normal operations.

Successful exploitation results in denial of service due to resource exhaustion (memory and buffer depletion) on affected Cisco Secure Firewall ASA and FTD devices. This disrupts SSL VPN connection processing, potentially halting VPN services until resources are restored or the device is manually reloaded. There is no impact to confidentiality or integrity reported.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch or official fix information is provided in the input data, users should monitor Cisco advisories for updates. Until a fix is available, consider limiting exposure of the VPN and management web servers to untrusted networks and apply any recommended temporary mitigations from Cisco.