A vulnerability in the shell access request mechanism of Cisco IOS XE Software could allow an authenticated, local attacker to bypass authentication and gain unrestricted access to the root shell of an affected device. The vulnerability exists because the affected software has insufficient authentication mechanisms for certain commands. An attacker could exploit this vulnerability by requesting access to the root shell of an affected device, after the shell access feature has been enabled. A successful exploit could allow the attacker to bypass authentication and gain unrestricted access to the root shell of the affected device.