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Of Encrypted Hard Drives and "Evil Maids"
Schneier has a blog piece about Joanna Rutkowska's "evil maid" attack, demonstrated earlier this month against TrueCrypt. "The same kind of attack should work against any whole-disk encryption, including PGP Disk and BitLocker. ... [A] likely scenario is that you leave your encrypted computer in your hotel room when you go out to dinner, and the maid sneaks in and installs the hacked bootloader. ... [P]eople who encrypt their hard drives, or partitions on their hard drives, have to realize that the encryption gives them less protection than they probably believe. It protects against someone confiscating or stealing their computer and then trying to get at the data. It does not protect against an attacker who has access to your computer over a period of time during which you use it, too."
Offhand, i'd say any prominent high-class hotel that might be used by foreign businessmen on a trip.
I mean, you do have a point, bob the middle manager isn't that important. However there are quite a few business people who this really would be that important to. Corporate espionage is high, and you know china has been doing focused attacks over the network.
Sneakernet is always faster, so if they can train up a few pretty women, pay them a decent programmers wage to have them steal stuff that is the work of 10 engineers or even hundreds, that's a pretty sound economic payoff don't you think?
I think stuff like this has it's purpose, and those who really are at risk need to be educated about it. For the other 95% of us, i think it's useful info to be aware about, just like don't leave your purse out visible in your car. Sure it probably won't happen, but there are always people who would.
You never realize how much manually made unmanaged "linked" lists suck, till you have src.link.link.link.link...
If you are the kind of person that are in the danger zone of this happening (not that you would leave a computer with such sensitive information in your hotel room.); You would probably feel a lot better if you were able to checksum the bootloader when returning, maybe from an external usb drive. This would offcourse run it's own OS, not being done from the bootloader(for obvious reasons).
Doolittle :
Bomb no.20 : To explode of course.
You vastly underestimate the number of people traveling internationally and engaged in activities that the host governments find to be of interest.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
I didn't read the RTFA, but aren't MSFT's BitLocker supposes to validate the boot path (from BIOS code to bootloader up to the BitLocker decrypter) with the help of the TPM chip?
Bob the middle manager isn't that important, but Bob routinely sends email to Dave the director and Charles the CxO. By trojaning Bob's computer you can start to build a pretty decent profile of the corporate activities going on within, and above, Bob's department ... including travel schedules of some other bigger fish in the corporate pond.
Do this to 3 or 4 Bobs, and pretty soon you'll have an understanding of the corporate org chart, upcoming projects, and most importantly you'll be able to target your future EvilMaid attacks with pinpoint accuracy.
If libertarians are so opposed to effective government, why don't they all move to Somalia?
Evil maids are easy to spot because of their goatees.
Mother, do you think they'll like this sig?
You can see why it's called the "evil maid" attack; a likely scenario is that you leave your encrypted computer in your hotel room when you go out to dinner, and the maid sneaks in and installs the hacked bootloader. The same maid could even sneak back the next night and erase any traces of her actions.
Maybe if she's an idiot. Once you've installed your own bootloader, it can neatly remove itself. (After installing malware, or transferring the encryption keys and data it needs over the network.) Why in the world would the maid unnecessarily repeat the riskiest part of the entire attack?
But more to the point, it must be a slow week. Why are "serious" security researchers even wasting time on something this obvious? Of course your software-based hard disk encryption is hosed in the event that an attacker gets hold of your machine and can alter the bootloader. Hell, the really sophisticated bad guys aren't even going to do anything this difficult or risky. After all, the encryption key has to be in RAM somewhere whenever you're using software-based encryption (hardware encryption excluded). A well-engineered piece of malware will recover it, and two-factor authentication isn't going to help you.
Even trusted boot will only get you so far against a motivated adversary with this much sophistication. Don't leave your vital computing equipment behind in your hotel room.
Except it's not quite like that. It sounds more like you lock your door and leave to get groceries. Before you get back, someone comes up to the door and installs something that can scan the key that is used to unlock the door. That person leaves, you return, unlock the door, and go in. You later head out again, locking the door behind you, and that other person comes up, recovers their device, makes a duplicate key based on the device's contents, and now has access to your home.
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-