Cisco Secure Firewall ASA and FTD Software Remote Access SSL VPN Denial-of-Service Vulnerability

A denial-of-service vulnerability has been identified in the Remote Access SSL VPN feature of Cisco Secure Firewall ASA Software and Secure FTD Software. This vulnerability allows an unauthenticated, remote attacker to cause the device to reload unexpectedly, leading to a denial-of-service condition. The issue arises from insufficient error checking when processing SAML messages, which could be exploited by sending crafted SAML messages to the SAML service.

Impact

Exploitation of this vulnerability causes the device to reload unexpectedly, creating a denial-of-service condition that may require a manual reboot.

Remediation

Cisco has released software updates to address this vulnerability. Instructions for upgrading Cisco Secure FTD devices are available in the Cisco Secure FMC upgrade guide. For Cisco Secure Firewall ASA, consult the Cisco Secure Firewall ASA Upgrade Guide and use the Cisco Software Checker to determine the best release.