Work flow: 1. Update to PHP 5.5 will automatically update the Apache Server from 2.2 to 2.4 2. New security setting is added to 2.4 3. Need to rename vHost file with .conf extension and a2ensite it.
To deal with new security issue, it is required to add "Require all granted" inside the vHost file and prevent from editing (or commenting out) the original apache2.conf