For some less click-bait-y information, check out any of the "Car Hacking Village" videos from the past 5 DefCons. They go into great detail about what new vehicles actually do.
For example there was an extended period of time where any asshole could make themselves into an admin and get, and change, information on ANY car sold by a particular manufacture: https://www.youtube.com/watch?v=qNuS0rvqc8c