"Evil Maid" Attacks on Encrypted Hard Drives

your right but how many people would actually go that far. Bringing a computer to a expert or lab i dont know thats sounds pretty extreme. If someone is that determined to get your stuff then your screwed anyways because he will eventually regardless what you would do

 

or you can just change passwords everytime you use the computer

 

FYI -- PGP takes precautions to minimize the likelihood of success of an “extract-from-RAM” strategy...

 

That's all well and good, but it's simply a reduction of risk. They're not completely eliminating the vulnerability. I think it's the same with the MBR protection. The risk isn't completely eliminated, just reduced.

Regarding the bit flipping, that probably won't be effective at all against an attack using DMA. It might be effective against RAM freezing.

There's also something to be said for a minimalist strategy.

 

Correct. However, when choosing between a mitigated risk and an uncontrolled risk, the former is obviously to be preferred.

Not sure that I understand the “minimalist strategy.” Can you kindly elaborate? (Thank you.)

 

This is a quote from http://blog.pgp.com/index.php/category/pgp_advisory_board/page/2/

I'm surprised to hear this on that site, but it's entirely correct. I have to say the honesty of Jon Callas seems to be second to none. So, I'm not going to go any further or attempt to use his words against him. Suffice it to say, there's no software FDE that protects against this.

http://en.wikipedia.org/wiki/KISS_principle

There's no need to try to fix a problem if you don't have a complete solution. It just adds extra code and extra complexity.

 

i run most progs from memory stick and save onto same stick or external drive which i unplug and take with me so all evil maid would see is an operating system

 

A very interesting blog post, indeed! As Callas states, “This is a hardware problem, and comprehensive solutions for it require hardware support.” The software approach implemented by PGP can’t overcome this limitation, but it may be a (small) step in the right direction. Consider: since the publication of Callas’ blog post, PGP has added its anti-burn-in system to the PGP Whole Disk Encryption product, an indication of the company's perspective that the approach “might be a partial amelioration.”

On a more general point, I disagree with the argument that if a privacy solution is imperfect, then it is therefore without merit or value. The objective isn’t to achieve perfection -- rather, it is to maximize “total protection,” which may be conceived as a sum of the products of the (a) probability of a threat occurring and (b) the probability of the solution against that threat being effective. As long as the latter quantity is greater than zero, "total protection" will be enhanced -- and, it is rare indeed that any solution to a privacy problem is without limitations.

 

can't you just scan the usb ports for malware when you boot up. Wouldnt that tell if a evila maid was installed