[DoingIsLearning]

Just for clarity because this Jeep example comes up quite often when talking about cars:

I don't know any vehicle with connectivity (other than Jeep and maybe Ford?), which does not have safety critical CAN/FlexRay buses segregated from driver facing 'infotainment' systems.

What that means is that the network bus in which your 'compromised' infotainment system is able to operate is completely separate from Engine, ABS, AEB, ESP, Airbags etc.

The solutions vary but there is usually a physical gateway that prevents a passthrough MITM attacks, so you cannot simple send a message frame from your infotainment pretending to be an AEB module requesting emergency braking to your ABS system.