Heat Hack
Heat Hack

A team of UC San Diego security researchers presented a paper on how your Automatic Teller Machine (ATM) pin code can be stolen using the heat that our fingers leave behind. With the help of a digital infrared camera, the person immediately following you can know the keys you pushed, with 80% accuracy.

Frightened? Don’t worry! There are some drawbacks to this method of stealing ATM pins.

Even if the criminal can determine the digits pressed, it is very difficult for him to know the order in which they were pressed. That means he will have to use different combinations of the 4 digits. The second drawback to this ATM pin theft using the heat left behind is that it works only on plastic keypads. This is because if the keypad is made of metal, it gives off too much heat noise that the IR camera cannot distinguish accurately which keys are pressed.

And most of all, a good IR camera that fits this purpose will cost something around $18,000. If one has so much money to get hold of such a costly camera, then I seriously doubt that he will go for stealing ATM pins!

But this does not change the simple truth that our ATM pins are vulnerable to this ‘Heat Hacking’. This type of hacking is not limited to ATM machines, but can be done on keypad safes, security doors, keypad activated garage doors or car doors.

But we can always eliminate the little chance of pin theft by just placing our hand over the entire keypad after entering the ATM pin so that heat is equally given to all the keys in the ATM keypad. This simple step can ruin all the hacking plan of the suspected ‘criminal’ just behind you at the ATM. Do it just as a precaution!



  1. interesting fact, but it shows variation in the camera about the heat. that we can assume the least heat point is the button pressed first.