The PacTec Security Conference in Tokyo had something interesting show up. A countermeasure against drones that allows you to take control of any craft using the popular DSMx protocol. According to Ars Technica, DSMx transmitters and receivers exchange a key to prevent interference between adjacent systems. The key isn’t protected very well so by observing traffic and applying a little brute force, you can recover the key (which is set when the transmitter binds to the aircraft).
What’s more is a timing vulnerability allows the rogue transmitter to lock out the legitimate one. You can see a demonstration of the system, called Icarus, in the video below.
This could start an escalating technology war. It is easy to envision a market for a safe drone countermeasure (after all, just jamming one might crash it into something you won’t like; much nicer to take control of the machine and land it so you can impound it). However, it is easy to see that modifications to the protocol could render Icarus unusable. Until researchers find the next vulnerability, at least.