Cyber-intruder sparks response, debate

The first sign of trouble was a mysterious signal emanating from deep within the U.S. military’s classified computer network. Like a human spy, a piece of covert software in the supposedly secure system was “beaconing” — trying to send coded messages back to its creator.

An elite team working in a windowless room at the National Security Agency soon determined that a rogue program had infected a classified network, kept separate from the public Internet, that harbored some of the military’s most important secrets, including battle plans used by commanders in Afghanistan and Iraq.

The government’s top cyberwarriors couldn’t immediately tell who created the program or why, although they would come to suspect the Russian intelligence service. Nor could they tell how long it had been there, but they soon deduced the ingeniously simple means of transmission, according to several current and former U.S. officials. The malicious software, or malware, caught a ride on an everyday thumb drive that allowed it to enter the secret system and begin looking for documents to steal. Then it spread by copying itself onto other thumb drives.

via washingtonpost.com