This is why using a USB is an extremely bad idea. It is not just about rubberducky type of hacks, or being careful about autorun.inf. The USB protocol itself can be manipulated to do some really dark magic, even normal USB sticks (the ones you might have in your pocket right now) can get the firmware infected and turn any USB flashdrive into a rubberducky or even turning your USB flashdrive into a network adapter and sniffing your connections or even redirecting your traffic to do an MITM attack. So it is not about being careful about whose USB you allow to use in your computer, but about being paranoid about your OWN USB getting the firmware infected and spying yourself.
The USB is a security nightmare, if you want to learn the details about this, you can see the talk by the guys from srlabs.de:
The worst news of all? There are no ways of protecting against this type of attack.