A U.S. Secret Service memo obtained by MSNBC.com indicates that organized criminals are systematically attempting to subvert the ATM system and unscramble encrypted PIN codes. (Will Burgess ...

The FBI is warning of a potential ATM bank heist that could steal millions of dollars globally, and authorities now have good reason to believe the attack could be carried out within the coming days.

And when you think about it, ATM navigation is more than just your pin code alone (like when you input your withdrawal amount, for example), further confounding high tech thieves.

Entering ATM PIN backwards won't call the police A viral Facebook post advises ATM users being forced to withdraw cash to enter their PIN backwards to secretly call the police.