Some viruses modify the firmware of USB devices to trick the operating system into detecting the USB device as a keyboard.
The BadUSB Attack Prevention component prevents infected USB devices emulating a keyboard from connecting to the computer.
When a USB device is connected to the computer and identified by the application as a keyboard, the application prompts the user to enter a numerical code generated by the application from this keyboard, or using On-Screen Keyboard (if it is available). This procedure is known as keyboard authorization. The application allows use of an authorized keyboard and blocks a keyboard that has not been authorized.