Cars are offering more and more features to keep drivers and passengers connected while they're on the road. While most drivers appreciate being able to make calls, choose their own entertainment or get social media alerts on the road, all that connectivity has a downside. The more connected a car is, the more vulnerable it could be to computer hacking.

Chris Valasek and Charlie Miller received an $80,000 Defense Advanced Research Projects Agency (DARPA) grant to explore just what hacklers could do if they gained control of a car. Using a Ford Escape and Toyota Prius, the pair demonstrated for Forbes what their hacks could do to a car, including causing brake failure, blasting the horn and even turning the wheel.

The Ford Escape (Ford Motor Company)

While that sounds terrifying, in order to do it, Valasek and Miller had to physically connect their computers to the cars. NPR reports that while both Ford and Toyota take the research seriously, the companies point out that most people would notice if a hacker wired a computer to their car. However, other researchers have been able to enter a car's computer system remotely.

The New York Times reported in March 2011 that researchers from the University of Washington and the University of California, San Diego, had gained remote access to various car systems. Though the team didn't show they could wreak the kind of havoc Valasek and Miller did, the Times writes, "Because many of today’s cars contain cellular connections and Bluetooth wireless technology, it is possible for a hacker, working from a remote location, to take control of various features — like the car locks and brakes — as well as to track the vehicle’s location, eavesdrop on its cabin and steal vehicle data, the researchers said. They described a range of potential compromises of car security and safety."

Even though researchers have shown that they can gain access to cars, the odds of tonight's commute turning into hacker-orchestrated chaos are low. Jalopnik points out that hacking more than one car at once is a much taller order than just taking control of one.

The Toyota Prius (Toyota Motor Corporation)

NPR explains, "It's unlikely, however, that malicious hackers will take advantage of these attacks any time soon. All cars don't all use one operating system and they don't all speak one single language. So before a hacker can take control, he or she has to learn the specific code that runs the systems for that specific car."

If you're concerned about someone hacking your car, you can avoid it by driving an older car with limited electronic systems. Of course, that means giving up features like antilock brakes, air bags, stability control and traction control. All of those features have been proven to lower the risk of being in an accident, while the real-world risk of being hacked hasn't been fully proven yet.

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