The Defense Department has banned the use of removable flash media and storage devices from all government computers, according to a series of notices put out by the services this week.
The action comes following reports that a worm virus known as "Agent.btz" was discovered infecting some DOD networks, according to Wired magazine.
LeAnne MacAllister, 5th Signal Command’s director of Strategic Communication, U.S. Army Europe, said this week that leadership directed her office to stop using thumb drives — portable memory devices used to store or transfer files.
A separate internal Army e-mail told some government computer users across Europe to turn in all removable media devices.
In an e-mail sent Thursday to all Navy European customers in Naples, officials said "effective immediately all USB Thumb drives, memory sticks/cards and camera flash cards are PROHIBITED from use on any Navy Network (NIPR or SIPR) until further notice."
A worldwide directive issued Thursday by the Marine Corps offered similar restrictions.
"The only authorized media for use on DOD networks is media purchased and provided by the government," the Marine announcement said. "Under no circumstances will personally owned removable media be considered mission essential or used on government networks."
DOD officials at the Pentagon would not confirm the ban.
For security reasons, DOD officials won’t discuss "specific measures commanders in the field may be taking to protect and defend our networks," said Air Force Lt. Col. Eric Butterbaugh, a DOD spokesman.
But Wired magazine, citing an internal Army e-mail on its online edition Wednesday, said the ban comes from the commander of U.S. Strategic Command and applies to both the secret SIPR and unclassified NIPR nets.
The worm virus "Agent.btz" is a variation of an older worm that copies itself to removable USB drives from infected computers and then spreads itself to whatever new systems it is connected to through USB ports, Wired reported.
The worm seriously degrades computer performance by copying itself to multiple programs.
The ban includes memory sticks, thumb drives and camera flash memory cards, according to the Marine Corps directive. External hard disk drives are not included in the ban.
Butterbaugh said DOD’s Global Information Grid includes more than 17,000 local- and regional-area networks and approximately 7 million individual computers.