Cisco ASA and FTD Cross-Site Scripting (XSS) Vulnerability

A remote attacker, without authentication, can achieve partial data exposure, partial data tampering. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2022-05-03 under CISA BOD 22-01.

This is a Cross-Site Scripting (XSS) (CWE-79) vulnerability in Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). Multiple vulnerabilities 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 conduct cross-site scripting (XSS) attacks against a user of the web services interface of an affected device. The vulnerabilities are due to insufficient validation of user-supplied input by the web services interface of an affected device. An attacker could exploit these vulnerabilities by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or allow the attacker to access sensitive, browser-based information. Note: These vulnerabilities affect only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section. Exploitation requires remote network access, low attack complexity, no authentication required, and user interaction required.

Probably yes if any of these apply:

CISA confirms this CVE has been used in known ransomware campaigns. Added to the KEV catalog on 2021-11-03; federal agencies required to remediate by 2022-05-03.