A vulnerability in the Web Authentication feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a reflected cross-site scripting attack (XSS) on an affected device. This vulnerability is due to improper sanitization of user-supplied input. An attacker could exploit this vulnerability by persuading a user to click a malicious link. A successful exploit could allow the attacker to execute a reflected XSS attack and steal user cookies from the affected device.