USN-5252-2: PolicyKit vulnerability

USN-5252-2: PolicyKit vulnerability

USN-5252-1 fixed a vulnerability in policykit-1. This update provides
the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.

Original advisory details:

It was discovered that the PolicyKit pkexec tool incorrectly handled
command-line arguments. A local attacker could use this issue to escalate
privileges to an administrator.
Source: USN-5252-2: PolicyKit vulnerability