
Clever exploit of DRAM to attack disk encryption - ntoshev
http://glinden.blogspot.com/2008/02/clever-exploit-of-dram-to-attack-disk.html
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dfranke
I've been nervous about this sort of thing for a while. This is an email that
I sent to Bruce Schneier last month:

In your November article on laptop security, you mentioned the threat of
having your laptop grabbed out of hands while you're typing on it. Combined
with full-disk encryption, I use a very simple and effective defense against
this: configure the system to immediately lock the screen on transitions from
A/C power to battery. That way, the thief can't take your data any further
than the length of the power cord.

It's not completely fool-proof, of course: as long as the encryption key is
stored in RAM, it's theoretically possible to extract it, e.g., by transfering
the DIMM to special hardware while keeping it powered. But I've never heard of
anyone actually accomplishing this, and it's certainly beyond the ken of your
average identity thief and possibly even the FBI.

I use Linux exclusively, and there implementing this is a simple matter of
adding a hook into your acpid scripts. I'm not certain whether there's any
easy way to do it in Windows or Mac.

One more thought in a similar vein: a lot of modern laptops include
accelerometers so that they can make the hard drive protect itself if they
detect that they're being dropped. I wonder if it would feasible to use these
to detect that the laptop is being run-off-with.

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aston
Clever, but I think once someone malicious has physical access to your RAM,
you should consider _hitting_ them or calling the cops.

~~~
Prrometheus
What if they are the cops? What if they’re alone wherever you keep your
computers while you are not there?

~~~
cstejerean
once someone has physical access to your box all bets are off. You can try all
sorts of tricks to make it harder but at the end of the day the best defense
is keeping minimal amounts of data on computers that could fall in the wrong
hands.

