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Here’s a promotional security product designed by someone who knows nothing about security. The USB drive is “protected” by a combination lock. There are only two dials, so there are only 100 possible combinations. And when the drive is “locked” and the connector is retracted, the contact are still accessible.
Maybe it should be given away by companies that sell security theater.
Look at this new AES-encrypted USB memory stick. You enter the key directly into the stick via the keypad, thereby bypassing any eavesdropping software on the computer.
The problem is that in order to get full 256-bit entropy in the key, you need to enter 77 decimal digits using the keypad. I can’t imagine anyone doing that; they’ll enter an eight- or ten-digit key and call it done. (Likely, the password encrypts a random key that encrypts the actual data: not that it matters.) And even if you wanted to, is it reasonable to expect someone to enter 77 digits without making an error?
Nice idea, complete implementation failure.
EDITED TO ADD (3/4): According to the manual, the drive locks for two minutes after five unsuccessful attempts. This delay is enough to make brute-force attacks infeasible, even with only ten-digit keys.
So, not nearly as bad as I thought it was. Better would be a much longer delay after 100 or so unsuccessful attempts. Yes, there’s a denial-of-service attack against the thing, but stealing it is an even more effective denial-of-service attack.
Is this how the al-Mabhouh assassins got in?
Interesting blog post, with video demonstration, about an improved tool to open high security locks with a key that will just “form itself” if you insert it into the lock and wiggle it a little. The basic technique is a few years old, but the improvements discussed here allow the tool to open a wider variety of locks than before.
This is neat:
The Impressioner consists of a sensor that goes into the lock and sends information back to a computer via USB about the location of the lock’s tumblers—a corresponding computer program comes up with the code, depending on the make of car you’ve entered beforehand. Once you know the code, a key-cutting machine can use it to carve up a key.
Right now, it’s a prototype that only works on Ford car locks. The article points out that both locksmiths and thieves can use this device.
Another article.
EDITED TO ADD (2/16): How it likely works.
Reproducing keys from distant and angled photographs:
Abstract:
The access control provided by a physical lock is based on the assumption that the information content of the corresponding key is private—that duplication should require either possession of the key or a priori knowledge of how it was cut. However, the ever-increasing capabilities and prevalence of digital imaging technologies present a fundamental challenge to this privacy assumption. Using modest imaging equipment and standard computer vision algorithms, we demonstrate the effectiveness of physical key teleduplication—extracting a key’s complete and precise bitting code at a distance via optical decoding and then cutting precise duplicates. We describe our prototype system, Sneakey, and evaluate its effectiveness, in both laboratory and real-world settings, using the most popular residential key types in the U.S.
Those of you who carry your keys on a ring dangling from a belt loop, take note.
Texas Instruments’ calculators use RSA digital signatures to authenticate any updates to their operating system. Unfortunately, their signing keys are too short: 512-bits. Earlier this month, a collaborative effort factored the moduli and published the private keys. Texas Instruments responded by threatening websites that published the keys with the DMCA, but it’s too late.
So far, we have the operating-system signing keys for the TI-92+, TI-73, TI-89, TI-83+/TI-83+ Silver Edition, Voyage 200, TI-89 Titanium, and the TI-84+/TI-84 Silver Edition, and the date-stamp signing key for the TI-73, Explorer, TI-83 Plus, TI-83 Silver Edition, TI-84 Plus, TI-84 Silver Edition, TI-89, TI-89 Titanium, TI-92 Plus, and the Voyage 200.
Moral: Don’t assume that if your application is obscure, or if there’s no obvious financial incentive for doing so, that your cryptography won’t be broken if you use too-short keys.
Using a 3D printer. Impressive.
At the end of the day he talked the officers into trying the key on their handcuffs and … it did work! At least the Dutch Police now knows there is a plastic key on the market that will open their handcuffs. A plastic key undetectable by metal detectors….
EDITED TO ADD (10/12): Additional comments from the author.
Last year, I wrote about the increasing propensity for governments, including the U.S. and Great Britain, to search the contents of people’s laptops at customs. What we know is still based on anecdote, as no country has clarified the rules about what their customs officers are and are not allowed to do, and what rights people have.
Companies and individuals have dealt with this problem in several ways, from keeping sensitive data off laptops traveling internationally, to storing the data—encrypted, of course—on websites and then downloading it at the destination. I have never liked either solution. I do a lot of work on the road, and need to carry all sorts of data with me all the time. It’s a lot of data, and downloading it can take a long time. Also, I like to work on long international flights.
There’s another solution, one that works with whole-disk encryption products like PGP Disk (I’m on PGP’s advisory board), TrueCrypt, and BitLocker: Encrypt the data to a key you don’t know.
It sounds crazy, but stay with me. Caveat: Don’t try this at home if you’re not very familiar with whatever encryption product you’re using. Failure results in a bricked computer. Don’t blame me.
Step One: Before you board your plane, add another key to your whole-disk encryption (it’ll probably mean adding another “user”)—and make it random. By “random,” I mean really random: Pound the keyboard for a while, like a monkey trying to write Shakespeare. Don’t make it memorable. Don’t even try to memorize it.
Technically, this key doesn’t directly encrypt your hard drive. Instead, it encrypts the key that is used to encrypt your hard drive—that’s how the software allows multiple users.
So now there are two different users named with two different keys: the one you normally use, and some random one you just invented.
Step Two: Send that new random key to someone you trust. Make sure the trusted recipient has it, and make sure it works. You won’t be able to recover your hard drive without it.
Step Three: Burn, shred, delete or otherwise destroy all copies of that new random key. Forget it. If it was sufficiently random and non-memorable, this should be easy.
Step Four: Board your plane normally and use your computer for the whole flight.
Step Five: Before you land, delete the key you normally use.
At this point, you will not be able to boot your computer. The only key remaining is the one you forgot in Step Three. There’s no need to lie to the customs official; you can even show him a copy of this article if he doesn’t believe you.
Step Six: When you’re safely through customs, get that random key back from your confidant, boot your computer and re-add the key you normally use to access your hard drive.
And that’s it.
This is by no means a magic get-through-customs-easily card. Your computer might be impounded, and you might be taken to court and compelled to reveal who has the random key.
But the purpose of this protocol isn’t to prevent all that; it’s just to deny any possible access to your computer to customs. You might be delayed. You might have your computer seized. (This will cost you any work you did on the flight, but—honestly—at that point that’s the least of your troubles.) You might be turned back or sent home. But when you’re back home, you have access to your corporate management, your personal attorneys, your wits after a good night’s sleep, and all the rights you normally have in whatever country you’re now in.
This procedure not only protects you against the warrantless search of your data at the border, it also allows you to deny a customs official your data without having to lie or pretend—which itself is often a crime.
Now the big question: Who should you send that random key to?
Certainly it should be someone you trust, but—more importantly—it should be someone with whom you have a privileged relationship. Depending on the laws in your country, this could be your spouse, your attorney, your business partner or your priest. In a larger company, the IT department could institutionalize this as a policy, with the help desk acting as the key holder.
You could also send it to yourself, but be careful. You don’t want to e-mail it to your webmail account, because then you’d be lying when you tell the customs official that there is no possible way you can decrypt the drive.
You could put the key on a USB drive and send it to your destination, but there are potential failure modes. It could fail to get there in time to be waiting for your arrival, or it might not get there at all. You could airmail the drive with the key on it to yourself a couple of times, in a couple of different ways, and also fax the key to yourself … but that’s more work than I want to do when I’m traveling.
If you only care about the return trip, you can set it up before you return. Or you can set up an elaborate one-time pad system, with identical lists of keys with you and at home: Destroy each key on the list you have with you as you use it.
Remember that you’ll need to have full-disk encryption, using a product such as PGP Disk, TrueCrypt or BitLocker, already installed and enabled to make this work.
I don’t think we’ll ever get to the point where our computer data is safe when crossing an international border. Even if countries like the U.S. and Britain clarify their rules and institute privacy protections, there will always be other countries that will exercise greater latitude with their authority. And sometimes protecting your data means protecting your data from yourself.
This essay originally appeared on Wired.com.
Encrypting your USB drive is smart. Writing the encryption key on a piece of paper and attaching it to the USB drive is not.
Sidebar photo of Bruce Schneier by Joe MacInnis.