This is an exploit for virtual servers (Score 5, Informative)

As many have pointed out, there's no real point to "exploiting" a machine that you already have full (root) access to - with one exception: virtual servers.

The whole 'danger' of this exploit is that it enables a virtual server's "privileged" "root" user to gain hypervisor access, which is equivalent to taking over the entire physical machine and any/all other virtual servers hosted on said machine.

If you don't run a virtual server farm, this exploit means absolutely nothing to you. If you do, it's a very easy, scary way whereby any of your "clients" can take over your physical machines and access all of the other virtual servers hosted on the same piece of hardware.