DJI Spark hijacking
DJI drones have been on the radar of the hacker community for quite a long time. The interest of its members revolves mostly around unblocking some features of drones, setting control channels of drones to a higher frequency, and removing such restrictions as flight altitude limits or strictly set no-fly zones. Moreover, there are piles of publicly available info about jailbreaking drones.
The most useful know-hows produced by the community are gathered in several Github cross-referenced repositories. Those striving for knowledge may also check the community wiki dji.retroroms.info. For quite a while the website has been accessible as a web archive only, but now the wiki is available again.