It's shell a program that spawns another running copy of itself, then they both spawn another copy of themselves each, then all 4 spawn another copy, ...
Actually, you can't put them in the computer where I work. Safety protocols, you can't use any devices except that but you're provided for you by the company
No you can't, every device has to be approved by the company, and they need to know exactly what you're using this device for. It's so strict that literally I can't even plug my phone into a computer if I forget to bring my wall plug, in order to charge it I mean.
A USB flash drive with viruses on will probably be pretty ineffective; someone would need to run the virus manually without AV picking it up which is pretty unheard of. Plus, any organisation worth it's salt will have a policy that automatically blocks drives that aren't encrypted with a company-issued encryption key.
The real risk is that a device like this can emulate any USB device, including disks, keyboards, monitors, serial devices, etc. So you plug in the key and in a split second it opens a terminal and types a dozen especially tasty commands...