Freezing the Cold-Boot AttackAugust 1, 2008 – 1:14 PM
A security expert who helped pioneer some of the research behind the recent cold-boot attack discovery by researchers at Princeton University will reveal next week at Black Hat USA the technical details of methods he developed for protecting an encrypted laptop from the hack.
The software-based techniques defend against so-called cold boot attacks on machines that were recently shut down or are in hibernate or screen-lock modes, by protecting the encryption keys themselves. The cold boot attack basically takes advantage of a brief window when cryptographic keys remain stored in DRAM at shutdown or in sleep mode to then retrieve those keys.
To date, most preventative measures have required users to turn off their machines when they were finished, and to then sit and watch them for about five minutes, says Patrick McGregor, CEO of BitArmor, which has built technology to defend against cold-boot attacks.
“Some people have dismissed the cold boot attack as a minor issue, but that’s not true. To pull off the attack, all you have to do is literally stick a USB into the laptop you get your hands on,” McGregor says. “It doesn’t require any technical skill — you can easily get automated tools to perform the attack for you.”
The epidemic of stolen laptops has brought the vulnerability to the fore: last year, over 600,000 laptops were stolen from airports alone, McGregor notes. “And all the information on those machines is vulnerable to cold-boot attacks.”