Yeah, I was just giving that as an interesting example. ESX/ESXi has had it's
fair share of exploits too but i'm not aware of any infections that make use of them. If it was connected to the net (I saw your box wasn't) then it could still be possible for an outside attacker to elevate themselves to full control of the box rather than the one virtual machine, if you run the old versions or a new exploit is found. All manual work though.
Was just making the point that hypervisors were not 100% foolproof like they are supposed to be.
Was thinking of getting a microserver to run ESXi on and just have lots of servers on it as vm's running all at the same time.