CVE-2021-34704

Name of the Vulnerable Software and Affected Versions Cisco Adaptive Security Appliance (ASA) Software (affected versions not specified) Cisco Firepower Threat Defense (FTD) Software (affected versions not specified)

Description A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a malicious HTTPS request to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. The estimated number of potentially affected devices worldwide is 242,070, according to Shodan.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability. As a temporary workaround, consider restricting access to the web services interface to minimize the risk of exploitation. Avoid using the vulnerable web services interface until the issue is resolved. To prevent exploitation, it is recommended to apply the update provided by Cisco.