Updates from Karsten’s BadUSB

18 November 2014

Karsten Nohl’s research on USB security is covered in The Good News and Bad News About USB Security — Only half have an unpatchable flaw, but we don’t know which half, Wired and Slate Magazine, 12 Nov 2014:

Nohl’s BadUSB attack, which he revealed at the Black Hat security conference in August, takes advantage of the fact that a USB controller chip’s firmware can be reprogrammed. That means a thumb drive’s controller chip itself, rather than the Flash storage on that memory stick, can be infected with malware that invisibly spreads to computers, corrupts files stored on the drive, or quietly begins impersonating a USB keyboard to type commands on the victim’s machine.

Nohl says that means combatting BadUSB will require device-makers to clearly label the chips their products use. “You’d never get away with this in a laptop. People would go crazy if they bought a computer and it wasn’t the chip they saw in the review they read,” he says. “It’s just these USB devices that come as black boxes.”

For the technical details, see https://opensource.srlabs.de/projects/badusb.