content: Interesting idea, but Ethernet over power-line doesn't work like that. Typically you need to have a device at each end where you plan on terminating the Ethernet. You can't just strip off an RJ45 connector and jam it into the wall socket and expect a signal, so why would you expect to plug in your AC adapter and expect Ethernet? Because USB-C? Nah.  edit In theory, I could see a company design a power-adapter/Ethernet over power-line adapter. However, in my opinion, we're closer to the borrowing unknown charger cables vector.  If you're really worried about your proposed attack vector then I would recommend to start looking for a USB-C data condom similar to this. I'm more worried about cheap USB-C cables people will buy to save a buck, and ultimately damage their pricey computer.