A lot of the "safe" code written in embedded systems is only safe because the inputs are already safe. You don't get to exploit any bugs in a parser when the messages are created by a system under your control. Cars, planes, trains, medical devices, etc. don't really have interfaces to the outside world that can easily be exploited. Those interfaces they have get exploited. See for example https://www.wired.com/2015/07/hackers-remotely-kill-jeep-hig...