A vulnerability in the web-based Wireless Controller GUI of Cisco IOS XE Software for Cisco 5760 Wireless LAN Controllers, Cisco Catalyst 4500E Supervisor Engine 8-E (Wireless) Switches, and Cisco New Generation Wireless Controllers (NGWC) 3850 could allow an authenticated, remote attacker to elevate their privileges on an affected device. The vulnerability is due to incomplete input validation of HTTP requests by the affected GUI, if the GUI connection state or protocol changes. An attacker could exploit this vulnerability by authenticating to the Wireless Controller GUI as a Lobby Administrator user of an affected device and subsequently changing the state or protocol for their connection to the GUI. A successful exploit could allow the attacker to elevate their privilege level to administrator and gain full control of the affected device. This vulnerability affects the following Cisco products if they are running Cisco IOS XE Software Release 3.7.0E, 3.7.1E, 3.7.2E, 3.7.3E, 3.7.4E, or 3.7.5E: Cisco 5760 Wireless LAN Controllers, Cisco Catalyst 4500E Supervisor Engine 8-E (Wireless) Switches, Cisco New Generation Wireless Controllers (NGWC) 3850. Cisco Bug IDs: CSCvd73746.