Feeds

Security boffins unveil BitUnlocker

Disk encryption decrypted

Protecting against web application threats using SSL

BitLocker, meet BitUnlocker.

Word arrives from The Electronic Frontier Foundation that a crack team of researchers - including the Foundation's own Seth Schoen - have discovered a gaping security flaw in everyday disk encryption technologies, including Microsoft's BitLocker as well as TrueCrypt, dm-crypt, and Apple's FileVault.

If a machine is screen-locked or left in sleep or hibernation mode, Schoen and his cohorts proclaim, an attacker can circumvent disk encryption simply by powering the machine down and quickly re-booting to an external hard drive.

You see, DRAM tends to retain data for up to a minute after power down. When a sleeping machine is "cold booted," its encryption keys stay right there in memory - and they're ripe for the taking.

So, sleeping machines are vulnerable even if they're left alone for a matter of minutes. "Let's say you're in a coffee shop and you leave your Vista notebook screen-locked and tied to a table while you take a trip to the bathroom," researcher Jacob Appelbaum told The Reg. "All I would have to do is force a reboot to a USB drive running our custom software, and I could work around BitLocker."

Yes, their custom software is called BitUnlocker. You can see it in action here.

With certain types of DRAM, a simple cold boot won't do the trick. Data fades too quickly after power down. But Appelbaum and company have also shown that retention rates can be extended by quickly cooling the memory. All they have to do is open up the machine and spray on a little canned air.

What if BitLocker is used in tandem with a TPM (trust platform module) security chip? According to Applebaum, this could mean the machine is even more vulnerable to an UnBitLocker attack. "When a machine boots, it immediately takes the encryption keys out of the TPM," he says, "and puts them into memory." In other words, when there's a TPM in place, Appelbaum can pull his trick on a machine that's already been powered off.

When we say gaping, we mean gaping. ®

Update

Originally, our article said that researchers put the freeze on RAM by spraying liquid nitrogen. Liquid nitrogen was used in some tests, but not in this way.

Reducing the cost and complexity of web vulnerability management

More from The Register

next story
Early result from Scots indyref vote? NAW, Jimmy - it's a SCAM
Anyone claiming to know before tomorrow is telling porkies
TOR users become FBI's No.1 hacking target after legal power grab
Be afeared, me hearties, these scoundrels be spying our signals
Jihadi terrorists DIDN'T encrypt their comms 'cos of Snowden leaks
Intel bods' analysis concludes 'no significant change' after whistle was blown
Home Depot: 56 million bank cards pwned by malware in our tills
That's about 50 per cent bigger than the Target tills mega-hack
Hackers pop Brazil newspaper to root home routers
Step One: try default passwords. Step Two: Repeat Step One until success
NORKS ban Wi-Fi and satellite internet at embassies
Crackdown on tardy diplomatic sysadmins providing accidental unfiltered internet access
UK.gov lobs another fistful of change at SME infosec nightmares
Senior Lib Dem in 'trying to be relevant' shocker. It's only taxpayers' money, after all
Critical Adobe Reader and Acrobat patches FINALLY make it out
Eight vulns healed, including XSS and DoS paths
Spies would need SUPER POWERS to tap undersea cables
Why mess with armoured 10kV cables when land-based, and legal, snoop tools are easier?
prev story

Whitepapers

Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.