Pentagon still mum on thumb drive ban

The Defense Department has not officially explained why it banned thumb drives from its networks, but some services have hinted at the risk the removable devices pose.

An article posted on the Web site operated by Andersen Air Force Base in Guam informed users that the devices were prohibited because more than 40 percent "of all viruses and worms are transferred from one computer to another by removable media like thumb drives."

And in a message sent on Nov. 20 to Marine commands, Marine Brig. Gen. George Allen said the ban on the use of removable storage devices on Marine networks "is predicated on a credible and serious threat to USMC networks."

While not addressing the prohibition on thumb drives directly, Pentagon spokesman Bryan Whitman said last week, "We are aware of a global virus for which there are some public alerts. . . . We've seen some of this on our networks. We're taking steps to identify and mitigate the virus."

Andersen told users that while thumb drives were the most commonly used form of removable media, "a virus or worm can be transferred through any removable media to include external hard drives, cell phones, digital cameras and even MP3 players that are connected to a computer." The Air Force has a servicewide ban on connection of any of these devices to its networks.

Their small size, portability and large storage capacity make thumb drives convenient, but also increase the chance that sensitive information can be compromised, Andersen warned computer uses. Thumb drives are easily misplaced, which makes them a target for thieves, especially since one thumb drive could contain hundreds of personnel records.

Rey Espinoza, a network administrator at Twentynine Palms, Calif., warned computer users who ignore the ban that they will be discovered through system scans and punished. If a "device or flash drive is connected to any computer on a Marine Corps network at the time that a scan is performed, it will be identified." he said. "If it's caught during a scan, that user's machine will be confiscated, and their account will be disabled, and the user will be subject to any action that will be taken after that."

Twentynine Palms will help end users transfer mission-critical files from thumb drives to CDs, Espinoza said.