More flash drive firms warn of security flaw; NIST investigates

Computerworld - SanDisk Corp. and Verbatim Corp. have joined Kingston Technology Inc. in warning customers about a potential security threat posed by a flaw in the hardware-based AES 256-bit encryption on their USB flash drives.

The hole could allow unauthorized access to encrypted data on a USB flash drive by circumventing the password authorization software on a host computer.

"It's really onerous. It's a stupid crypto mistake and they screwed up, and they should be rightfully embarrassed for making it," said cryptographer and computer security specialist Bruce Schneier.

Verbatim warned that the security flaw exists in its Verbatim Corporate Secure and Corporate Secure FIPS Edition series of USB flash drives; SanDisk revealed a threat related to its Cruzer Enterprise series of USB flash drives. Both companies issued online application upgrades to address the issue.

According to SanDisk and Verbatim, the security issue only applies to the application running on the host system; it doesn't apply to the drive itself or the drive's firmware. Computerworld reported earlier this week that Kingston had recalled its DataTraveler secure USB flash drives so it could update the devices because of the same issue. The Kingston models affected include the DataTraveler BlackBox, DataTraveler Secure-Privacy Edition and DataTraveler Elite-Privacy Edition.

All three companies claimed their USB drives had met security criteria set by the Federal Information Processing Standard (FIPS) 140-2. FIPS is a U.S. government standard used to accredit devices with encryption algorithms. The standard was developed by the National Institute of Standards and Technology and includes both hardware and software components. FIPS 140 covers four levels of security.

"There are lots of certifications out there, and they mean very different things," Schneier said. "These certifications are far more about marketing than they are about real security."

Storage companies tout FIPS 140-2 certification as part of their marketing materials, stating that their devices are secure enough for use by government agencies. Because of security problems in the past, however, the government has banned the use of removable flash media devices by its employees.

"What does the NIST certification mean? Is it a good standard or a bad standard? That certainly is the issue here," Schneier said. "If you look at the NIST certification, all it means ... is there's some level of tamper resistance in the hardware. Does it mean it's any good? No."

German security company SySS GmbH found the flaw when it tested the drives' security and designed code for each device that modifies the software running in the computer's memory, telling it to always authorize the password -- no matter who enters it or what it is.