"If you see any cops, I want you to mullet as fast as you can."
It's one of those scenes you just know James Cameron made up on the fly, because ATMs can't be that easy to hack in the real world -- otherwise, people would be doing it all the time. No, if real-life criminals want to steal money from an ATM, they need to go all low-tech and do something like steal the entire machine and get busy with a blowtorch, or blast it open with explosives:
The Real-World Hack:
Only it turns out that jackpotting an ATM is even easier than lil' John Connor made it look, even in a future that finds itself severely lacking in Atari laptops.
One pair of criminals in Pittsburgh reprogrammed an ATM to think it was dispensing $1 bills instead of $20s, netting themselves $1,540 in two days. And they didn't even need to plug in a laptop to do it -- they simply used the built-in keypad to reprogram the machine. Anyone watching them on the security camera would have thought they were just some of those people who hold up the ATM line when all we need to do is grab 20 bucks for lunch, goddammit.