Best malware ever
Defense Systems has a great explanation of the Stuxnet worm that is targeting industrial machines and may have been an attack against Iran's nuclear facilities. Kevin Coleman writes that the "Stuxnet worm was highly sophisticated - perhaps the most sophisticated attack that is known to the public thus far, leading some in the field to proclaim the piece of code the best malware ever."
A commenter on the article asks why critical machines would be connected to the public internet and made vulnerable to such attacks. Dark Reading points out that even if the machines are isolated, they can be breached using USB sticks:
PLCs and control systems had been considered relatively insulated from the outside world and attack because they aren't typically Internet-connected. But Stuxnet drove home the worst-kept secret that these systems still are connected to Windows or other machines that can get infected -- in this case, by a USB stick -- and therefore aren't as protected as they had seemed.
An easy solution would be to use Endpoint Security or Group Policy to block USB sticks unless they have built-in anti-virus protection like the Kanguru Defender Elite.