Modern cars have a lot of electronic controls.
Such as, if you have parallel parking assistant, the computer has control of the steering.
Almost all cars have anti-lock brakes. These are controlled by computers and can lock any individual brake.
Many cars are now including collision avoidance. And this is more controls on the car.
And, since the radio is hooked in the car's computer, it can get signals from radio waves.
A group of college kids sent a car into a ditch on command proving that this was doable.
And there are theories that several people have been killed by their cars.