A vulnerability in the web-based management interface of Cisco Adaptive Security Appliance (ASA) 9.1(6.11) and 9.4(1.2) could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the web-based management interface of an affected device, aka WebVPN XSS. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of an affected device. An attacker could exploit this vulnerability 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. Cisco Bug IDs: CSCve19179.