Hackers and hacking cars is bullshit. Yes they can do it. As always, anybody with physical access to a device can do anything they want to it; eventually. By physical access, I mean the turds that took over a jeep from ten miles away had access to the car and it's systems before the hack. They had a MAC address or other fixed electronic signature that they could sort out of the billions of signals floating through the air and single out the one data stream as a specific vehicle with a specific vulnerability. They also had specific knowledge that the cars telemetry system was paid up and operating. There is absolutely ZERO chance some dipshit dingdong can take over *your* car w/o days or weeks of preparations and your permission to do it; especially if you don't pay for OTA services.
Nobody, anywhere can just pick a convo out of a sprint network and say "that's the red jeep up ahead". Only the techno-feebs reporting news believe that.
This whole thing is just a bunch of feebs trying to scare people and extort money. Yes there are some specific problems with onStar. Its GM. WTF do you expect from the crown prince of clown cars? Hacking has nothing to do with it. Remote Start is a stupid idea that never should have been sold or bought. It's illegal in many states to leave a car running unattended for a *reason*. I don't know how GM gets away with it. But I digress, even OnStar doesn't work unless you pay for it; and why do you need services like that? Your cell phone doesn't work? You can't stop locking your keys in your car or you can't affor a locksmith for the one time you do?
This is as overblown as all the other hacker mythology. Media hysteria. The lay public thinks Abby Scuito and Timmy McGee can just click a few keys and "crack" any security anywhere; nevermind the incestuous Mr. Robot...in reality nobody can do shit without user stupidity, social engineering and/or physical access to the device being "hacked".
If you are actually afraid of this, you can take pills for it to calm you down.
OK, so a few people can, with sufficient expertise and equipment (like 10 people and exactly none of *you*), pop the locks on some VWs and some other some shit like that. I can do that too; with a glass hammer...lots quicker. Steal a car with keyless start or over-ride the ignition disabler? So what? I have insurance and police for that. It's much cheaper than all the bullshit needed to make it impossible(and won't stop it anyway). If someone really wants your car, all they need is a tow-truck.
Government? Really? You want Carnivore/Echelon/Prism in your car? Then you'll be really secure.
Get over it. Let the free market take care of itself and please keep Uncle Sam out of car systems.