Change those passwords - ABM fraud
An ATM in Virginia recently gave out twenties when it thought it was giving out fives. Seems the fraudster found the machine's manual online that included the codes to put the machine in operator mode, and the default operator password - then used that to reprogram the machine. It never ceases to amaze me that people don't change default passwords or set up initial security on various devices, despite the manufacturer's encouragement to do so.
I can perhaps understand when that happens to a typical consumer with a WiFi connection, but not for something like a bank machine. And putting an operator manual for a bank machine online might not be the best idea either.