Lock Picking And Security Disclosure


Slate is running an interesting article about taking new security approaches to lock vulnerabilities. In the past, lock makers such as Medeco have been able to quietly update their product lines to strengthen their security, but as movements such as Locksport International gain popularity and lock picking videos on YouTube become dime a dozen, lock makers can no longer rely on security through obscurity. It’s no question that an increased interest in this field helps lock manufacturers to create more secure products, but because patching these flaws often means changing critical features of the lock, it becomes a very expensive game of cat-and-mouse.

Traditional lock picking has employed the use of picksets, like the credit card sized set given out sold at The Last HOPE, but more recent methods of lock hacking have used bump keys or even magnets. However, as manufacturers make their locks less susceptible to picking and bumping, not even high-security locks will ward off someone determined enough to create a copy of the key, either by observing the original or using impressioning, as [Barry Wels] covered in a recent talk at HOPE 2008.

HOPE 2008: Methods Of Copying High Security Keys


[Barry Wels] is well known for his lockpicking talks, but this year he wanted to talk about how he copies high security keys. If a key blank is available, you could make a copy just by viewing the original. High security keys generally have profiles with more side cuts, which means you can guess at how deep a specific pin is by observing how many cuts it crosses. He also showed that you could imprint your arm with the key and use that as a guide. If a blank isn’t available, you could fill a similar key with solder and file that down.

[Barry] showed two different kits for casting keys. The first used soft clay in a clam shell to make an imprint of the original key. The form is then filled with a low melting point alloy (probably Wood’s metal) to create the new key. A second style uses a metal form and two part silicone to create the mold. This method works for most high security keys, but will not work on keys with active elements like sliders or magnets.

Finally, [Barry] talked about his favorite method: impressioning. Unlike picking a lock, when you’re done impressioning you have a funtional key. You start with key blank and file off the top layer. Place the blank in the lock and turn it till it jams. Then, you rock the key up and down. Observing the key under light you’ll see a small mark where each pin is. File a bit where the marks appear and repeat the process. You can’t use too much force or you might break the blank. This also works on dimple keys and as this video shows, laser cut keys. [Barry] highly recommends the impressioning book by [Oliver Diederichsen].

[photo: Rija 2.0]