The U.S. Secret Service is warning financial institutions about a recent uptick in a form of ATM skimming that involves cutting cupcake-sized holes in a cash machine and then using a combination of magnets and medical devices to siphon customer account data directly from the card reader inside the ATM.
According to a non-public alert distributed to banks this week and shared with KrebsOnSecurity by a financial industry source, the Secret Service has received multiple reports about a complex form of skimming that often takes thieves days to implement.
This type of attack, sometimes called ATM “wiretapping” or “eavesdropping,” starts when thieves use a drill to make a relatively large hole in the front of a cash machine. The hole is then concealed by a metal faceplate, or perhaps a decal featuring the bank’s logo or boilerplate instructions on how to use the ATM.