A security researcher hacked into ATMs made by Triton and Tranax and planted a rootkit that dispensed cash on demand. The rootkit even sets up a hidden pop-up menu that can be activated by special key sequence. The most impressive attack used the Dillinger remote ATM attack/admin tool s. tool came with a graphical UI that included features to Retrieve Track Data, or simply Jackpot!
Source: https://threatpost.com/hacker-demos-remote-attacks-against-atms-072810/74271/