The details ain't as simple as it sounds but the ATM are actually Windows PCs need to be running on XP then it has to be infected with a trojan virus called Ploutus.
The fraudsters then have to access the computer (ATM) innards and install their malware and hook it up to a mobile phone via a USB port and then they have a full control of the machine
Then all they are now required to do is to send a message to the planted ATM phone, it then translates the text into a network packet and sends it to the ATM. Ploutus then transforms the packets into command-line instructions.
Symantec’s Daniel Regalado said: “It may seem incredible, but this technique is being used in a number of places across the world at this time,”
The setup could last for a very long time if not caught because the phone is plugged in and is constantly recharging and never runs out of power.
Ploutus apparently affects only a single brand of ATM, but Symantec has not released the brand name. It did note that the Trojan, originally written in Spanish, now has an English-language variant, suggesting that the criminals behind it might hope to expand their operation.
What is indisputable is that, as Regalado wrote, “cybercriminals are targeting ATMs with increasingly sophisticated techniques.” But that would be true no matter which operating system an ATM runs.
Sources: Yahoo!