A vulnerability in the CLI of the Cisco StarOS operating system for Cisco ASR 5000 Series Aggregation Services Routers could allow an authenticated, local attacker to perform a command injection attack on an affected system. The vulnerability is due to insufficient validation of commands that are supplied to certain configurations in the CLI of the affected operating system. An attacker could exploit this vulnerability by injecting crafted arguments into a vulnerable CLI command for an affected system. A successful exploit could allow the attacker to insert and execute arbitrary commands in the CLI of the affected system. To exploit this vulnerability, the attacker would need to authenticate to an affected system by using valid administrator credentials. Cisco Bug IDs: CSCvg29441.