CAUTION -- DEVILS' ADVOCATE STATEMENT -- be careful, because now the bad computer-thief people can just as easily steal your car as they now steal your passwords and credit card numbers!
...and, I doubt NORTON, SAMANTEC, or LIFELOC will reimburse you for a cyber-stolen car.
So someone would need to know where you were/where you parked the car. Have a black key for your car, and crack your onstar credentials... this is so remotely possible I'm ruling it impossible