How to crack a master lock

http://www.markedwardcampos.com/index.php?/design/master-lock/

by yan • 17 years ago

84 43 17 years ago

NathanKP2• 17 years ago

Very fascinating and a good thing to keep in mind if I ever forget my combination lock number, thought that's unlikely. The only thing you would use this for is breaking into other people's locks. ;)

skolor3• 17 years ago

Not necessarily. It would take ~10-15 minutes of straight work to get this (more for your first few tries), so you can't really open a lock in a public place this way. On the other hand, it means you can pick up locks that the owner doesn't know the code to, and make them usable again by "recovering" the code.

icefox• 17 years ago

If social engineering taught me anything it is not only could I spent 15 minutes at the lock, but I could even print this out and tape it to the wall in front of me. I forgot my lock combo and am trying to recover it, thats all. Someone might even come over and help :)

ax0n• 17 years ago

Well, the information has been out there for more than a decade, but this is a really cool way to represent the process. There are also a lot of faster ways to get past a $5 Master combination lock, so this method is really only useful if you want to deduce the combination of a lock -- for instance, if you found one on the side of the road, or you cared about not only opening it, but being able to open it in the future without leaving an obvious sign of breach such as would occur using bolt cutters or a hacksaw.

uiohnuipb• 17 years ago

It's described in Feynman's biography 20 years ago - only for safes holding the designs of the atom bomb!

skolor3• 17 years ago

I've seen several of these now, but I like the way the information is presented here, usually its just a straight block of text, which is hard to read.

yan• 17 years ago

I mostly submitted because I liked the infographic aspect of it, not so much the information. That, as you say, has been around for a while.

skolor3• 17 years ago

I was not trying to downplay the submit, I was saying the infographic was an interesting way to display, it, one I hadn't seen before.

dlsspy• 17 years ago

I just use a shim.

pmorici• 17 years ago

I hear a quick blow with a mallet also works.

shrughes• 17 years ago

Why are all the comments mentioning picking the back of the lock now [dead]?

stanley_choad2• 17 years ago

A very good question. The same thing happened a little over a week ago, when a moderator deep-sixed all submissions of a particular thirtyseven signals post (sorry, I am avoiding regex bait now).

In fact, it appears that my account which attempted to post the aforementioned story is crippled, which is to say that all comments posted thereafter are auto-killed, yet do not appear so when I am logged in.

Another good question: does it bother anyone else that superuser-level moderation occurs in secret without any public recourse or justification?

tokenadult• 17 years ago

does it bother anyone else that superuser-level moderation occurs in secret without any public recourse or justification?

It is a good question. It doesn't bother me. Maybe that's because I've been in the role of an ordinary user on plenty of sites with little or no moderation, and I have also been in the role of a moderator (with varying degrees of moderation power and authority in the chain of command) on various sites. Most discussion sites need moderation. Most moderation actions don't need metadiscussion.

ryanwaggoner3• 17 years ago

At the very least, comments and stories that are killed should show the username of the user responsible. Is there any real justification for keeping it secret?

biohacker42• 17 years ago

You can also develop hyper sensitivity in you finger tips and feel when lock aligns. Lock pickers like this can allegedly detect the tip of a feather brushing against a toothpick being moved by the lock they are picking.

me325r4534534• 17 years ago

Dewalt drill.

lurkinggrue• 17 years ago

That takes all the fun out of it, unless you are into using power tools.

defdac2• 17 years ago

lol@first comment. Epic.

fuzzythinker• 17 years ago

give this dude some love, I had a good laugh after figuring out what that first comment meant.

defdac2• 17 years ago

Thanks =) I should have explained perhaps that the first comment on the page had noticed that the graphics that sould look like a finger pulling the lock looks like a.. well.. penis..

Zarathu• 17 years ago

Old.

Nwallins• 17 years ago

Originally from here: http://www.markedwardcampos.com/index.php?/design/master-loc...

It has been updated relative to the submitted version.

TapiocaSunshine2• 17 years ago

Thanks so much for the direct link, and the interesting discussion. I created the image, and I'm having a great time whizzing around the internets reading feedback.

Edit: If you're interested in some of the images that led up to this final: The process can be found at http://vdm3gd.wordpress.com/author/markofcca/

TapiocaSunshine2• 17 years ago

Also, I think I'm going to hang around here for a while : )

waterhouse• 17 years ago

This is a pretty good method, but sometimes it won't work. I've cracked several master locks in my life, and I found one for which the above method did not work--I kept getting the wrong 3rd digit, no matter how carefully I looked for the .5's. (Trying several hundred combinations in the process.) I recall another occasion when I gave up after finding two wrong 3rd digits (and trying 200 combinations), and another when my friend told me that the 3rd digit I found was wrong. With Google, I found this method, and it seems to work perfectly: http://www.angelfire.com/ma4/masterlockcrack/3rd-2.html

It gives the same answers as the first method most of the time. Think about it: if the centers of the ranges of the lock are in fact arranged in a group of four xx.5's (e.g. 2.5, 12.5, 22.5, 32.5), a group of four xx.0's, and a group of three xx.5's and an xx.0, which is what the first method predicts, then the second method should give the same 3rd digit.

I know nothing about the internal workings of the master lock, so I can't argue for either method on its own merits, but I do know this:

1. Using the first method, I've failed at least three times, and I don't think I suck at implementing it. Using the second method, I have not failed yet.

2. On that lock for which I, using the first method, failed to find the correct 3rd digit after about five tries, I found the correct 3rd digit with the second method on my first try. This digit was, in fact, one of the digits that I was quite sure was not correct according to the first method.

3. The second method is easier to do and to feel confident about. Instead of seeing what looks like a .25 and trying to decide whether I should call it a 0 or a .5, I just need to see whether this range is the same as that range and these other two ranges.

dunmalg• 17 years ago

Old news to me. I figured this out on my own 20-odd years ago. Then again, I'm a locksmith and that's the kind of stupid shit apprentice locksmiths do for fun. Thing is, to a locksmith it's not really a particularly useful trick. Any competent locksmith has access to the combination via the serial number. Back then we had to look them up in books, but now, I can access all that via a web site with my phone. It's like living in the future, I tell ya'.

KC8ZKF• 17 years ago

According to Master Lock, they have quit putting the serial number on the lock body. http://www.masterlock.com/faq/lostcombo.shtml

kasterma• 17 years ago

The code for my lock would not be found this way. Choosing the correct 3rd number (which obviously I know) my whole code does not appear in the suggestions to try.

grandalf• 17 years ago

Is the resolution of a master lock down to the actual number? Perhaps the exploit relies on close combinations also working?

dabent• 17 years ago

Worked in 5 minutes as advertised. Saved me a few bucks on a new lock. :-)

How to crack a master lock

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