It's called the CHT (Can Hacking Tool), and can be installed on any modern car's Controller Area Network 'within minutes' to run malicious code through the vehicle's system. Once hackers and / or thieves get into this network they can control lights, locks, steering and even brakes. It was created by Spanish security researchers Javier Vazquez Vidal and Alberto Garcia Illera. Continue reading for a video and more information.
According to The Daily Mail: "Many cars come with built-in software that run on an operating system in a similar way to phones and computers. The tool has four wires that are attached to the different outputs of a car's controller network. A $1 computer chip is used to bypass any encryption on the car before reading and writing data from the flash memory of the vehicle's engine control unit."