USN-4969-2: DHCP vulnerability

USN-4969-2: DHCP vulnerability

USN-4969-1 fixed a vulnerability in DHCP. This update provides
the corresponding update for Ubuntu 14.04 ESM and 16.04 ESM.

Original advisory details:

Jon Franklin and Pawel Wieczorkiewicz discovered that DHCP incorrectly
handled lease file parsing. A remote attacker could possibly use this issue
to cause DHCP to crash, resulting in a denial of service.
Source: USN-4969-2: DHCP vulnerability