XFS is a software interface and middleware standard used in banking devices, especially ATMs. It gives ATM applications a common way to talk to hardware such as the cash dispenser, card reader, receipt printer, and sensors, without needing custom code for every device model. In practice, XFS sits between the application layer and the physical machine controls.
This matters in cyber security because if an attacker gains control of the ATM operating system or application environment, XFS can become the path to the hardware. ATM malware may use XFS commands to tell the dispenser to release cash, turning a normal terminal into a jackpotting target. Defenders watch for abnormal XFS activity, restrict who can access the interface, and protect the ATM software stack with whitelisting, integrity checks, and strong logging.