A vulnerability in TACACS authentication with Cisco Wireless LAN Controller (WLC) Software could allow an authenticated, local attacker to perform certain operations within the GUI that are not normally available to that user on the CLI. The vulnerability is due to incorrect parsing of a specific TACACS attribute received in the TACACS response from the remote TACACS server. An attacker could exploit this vulnerability by authenticating via TACACS to the GUI on the affected device. A successful exploit could allow an attacker to create local user accounts with administrative privileges on an affected WLC and execute other commands that are not allowed from the CLI and should be prohibited.