# The Trick to Cracking a Master Combo Lock in Eight Tries or Fewer

By Sarah Zhang on at

Master combo locks aren't known as paragons of security. But damn, they look easy to crack. In a new video, hacker Samy Kamkar demonstrates a simple trick that he claims can break into most Master combo locks in just a few tries.

It’s so easy because Kamkar has done all the hard work for you, reverse-engineering the lock to narrow down the possible combinations to just  eight. All you have to do is go to input three numbers into Kamkar’s algorithm. Here’s how you get the numbers:

1. While lifting the locked shackle, turn the knob counterclockwise starting at the number 0. Between 0 and 11, the lock will “catch” in three places. Two out of three will be straddling a number. Record those two and ignore the one that is not.
2. Now lift the shackle again and turn the knob clockwise, until you encounter resistance. This is is your third number.

You type in these three numbers, and the algorithm spits out the first and third digits of the combination along with eight choices for the second. Now it’s just a matter of trying them all.

Go forth and do no evil. Let us know if this trick works for you.

[h/t Digg]