A couple of hackers show off a series of nasty new attacks on cars—with Forbes' Andy Greenberg behind the wheel.

"Stomping on the brakes of a 3,500-pound Ford Escape that refuses to stop--or even slow down--produces a unique feeling of anxiety. In this case it also produces a deep groaning sound, like an angry water buffalo bellowing somewhere under the SUV's chassis. The more I pound the pedal, the louder the groan gets--along with the delighted cackling of the two hackers sitting behind me in the backseat.

Luckily, all of this is happening at less than 5mph. So the Escape merely plows into a stand of 6-foot-high weeds growing in the abandoned parking lot of a South Bend, Ind. strip mall that Charlie Miller and Chris Valasek have chosen as the testing grounds for the day's experiments..."