CVE-2018-0428: High severity cisco web security appliance vulnerability

A vulnerability in the account management subsystem of Cisco Web Security Appliance (WSA) could allow an authenticated, local attacker to elevate privileges to root. The attacker must authenticate with valid administrator credentials. The vulnerability is due to improper implementation of access controls. An attacker could exploit this vulnerability by authenticating to the device as a specific user to gain the information needed to elevate privileges to root in a separate login shell. A successful exploit could allow the attacker to escape the CLI subshell and execute system-level commands on the underlying operating system as root. Cisco Bug IDs: CSCvj93548.