If you're overseas, guard your computer: A worm infected staff computers at the Bushehr nuclear power plant, Iranian officials said Sunday. The worm was likely uploaded from a thumb drive, and experts suspect it's the work of the U.S. or Israel, though cybersecurity expert James Lewis at the Center for Strategic and International Studies in Washington says it could have come from Britain, or even "the Russians or the Chinese for some weird reason." The attack highlights the vulnerability of state infrastructure to cyberattacks. A professor of national security and cyberexpert says, "The Stuxnet worm is a wake-up call to governments around the world. It is the first known worm to target industrial control systems and grants hackers vital control of vital public infrastructures like power plants, dams and chemical facilities." The attack also illustrates how dependent Iran is on foreign-made technology—although Western countries are similarly at risk, as many of the chips used to control their infrastructure are made in China and other foreign countries.