This is not a good news:
http://thehackernews.com/2013/09/Undetectable-hardware-Trojans.html
IMHO, There is no way to protect from this attack, without hardware open
source.
Only the Occam's razor[1] can help us: disconnect from the mains all
machines.
Bye
[1] -
http://pespmc1.vub.ac.be/OCCAMRAZ.html
--
Dario Lesca - sip:dario@solinos.it
(Inviato dal mio Linux Fedora19+Gnome3.8)