Begin forwarded message:

From: Jacob Appelbaum
Date: February 21, 2008 12:34:09 PM EST
To: David Farber
Subject: Cold Boot Attacks on Disk Encryption

Hi Dave,

With all of the discussions that take place daily about laptop seizures,
data breech laws and how crypto can often come to the rescue, I thought
the readers of IP might be interested in a research project that was
released today. We've been working on this for quite some time and are
quite proud of the results.

Ed Felten wrote about it on Freedom To Tinker this morning:
http://www.freedom-to-tinker.com/?p=1257

"Today eight colleagues and I are releasing a significant new research
result. We show that disk encryption, the standard approach to
protecting sensitive data on laptops, can be defeated by relatively
simple methods. We demonstrate our methods by using them to defeat three
popular disk encryption products: BitLocker, which comes with Windows
Vista; FileVault, which comes with MacOS X; and dm-crypt, which is used
with Linux. The research team includes J. Alex Halderman, Seth D.
Schoen, Nadia Heninger, William Clarkson, William Paul, Joseph A.
Calandrino, Ariel J. Feldman, Jacob Appelbaum, and Edward W. Felten."

"Our site has links to the paper, an explanatory video, and other
materials."

"The root of the problem lies in an unexpected property of today's DRAM
memories. DRAMs are the main memory chips used to store data while the
system is running. Virtually everybody, including experts, will tell you
that DRAM contents are lost when you turn off the power. But this isn't
so. Our research shows that data in DRAM actually fades out gradually
over a period of seconds to minutes, enabling an attacker to read the
full contents of memory by cutting power and then rebooting into a
malicious operating system."

Our full paper with videos and photos can be found on the Princeton
website: http://citp.princeton.edu/memory/

Regards,
Jacob Appelbaum

-=-=-=-=-=-


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Begin forwarded message:

From: Declan McCullagh
Date: February 21, 2008 3:57:43 PM EST
To: [EMAIL PROTECTED]
Cc: Jacob Appelbaum
Subject: Re: [IP] Cold Boot Attacks on Disk Encryption

Dave,

The paper published today makes some pretty strong claims about the
vulnerabilities of Microsoft's BitLocker, Apple's FileVault,
TrueCrypt, Linux's dm-crypt subsystem, and similar products.

So I put the folks behind it to a test. I gave them my MacBook laptop
with FileVault turned on, powered up, encrypted swap enabled, and the
screen saver locked.

They were in fact able to extract the 128-bit AES key; I've put screen
snapshots of their FileVault bypass process here:
http://www.news.com/2300-1029_3-6230933-1.html

And my article with responses from Microsoft, Apple, and PGP is here:
http://www.news.com/8301-13578_3-9876060-38.html

Bottom line? This is a very nicely done attack. It's going to make us
rethink how we handle laptops in sleep mode and servers that use
encrypted filesystems (a mail server, for instance).

-Declan


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