@freedomboxfndn
it doesn't matter if it has storage or not though. It's still a USB device, which thus could have firmware malware (keyboard/mouse emulation (see: #RubberDucky or #PHUKD)), or even hardware that physically fries the USB port (e.g. #USBKiller): https://www.bleepingcomputer.com/news/security/heres-a-list-of-29-different-types-of-usb-attacks/
Here's a List of 29 Different Types of USB Attacks

Researchers from the Ben-Gurion University of the Negev in Israel have identified 29 ways in which attackers could use USB devices to compromise users' computers.

BleepingComputer