Computer systems that control your car and its safety systems are open to attack from malicious hackers, according to experts.
US researchers under the lead of Professor Stefan Savage from the University of California-San Diego, and Tadayoshi Kohno from the University of Washington looked at how easy it was to attack and manipulate a car's computer systems.
The study has concluded that such systems in cars are 'fragile' and easily sabotaged.
Studies found that it was possible to turn off a car's brakes remotely. They also managed to subvert instruments, so that they gave misleading and incorrect readings.
Electronic brain is vulnerable
The study concentrated on the many electronic control units (ECUs) fitted throughout modern cars. It's estimated that most cars have approximately 100 megabytes of code spread across up to 70 ECUs.
While these units would usually just control part of a single system, the ECUs speak to each other allowing attacks on one to affect other systems throughout the vehicle. Malicious code inserted into ECUs and spread around the 'network' could turn off other systems, such as seatbelt pre-tensioners and airbags.
The researchers instigated attacks on stationary and moving cars to see how much control they could assert by hacking the ECUs.
'We are able to forcibly and completely disengage the brakes while driving, making it difficult for the driver to stop,' wrote the research team. 'Conversely, we are able to forcibly activate the brakes, lurching the driver forward and causing the car to stop suddenly.'
The study concluded that virtually every in-car system was vulnerable to external manipulation, including brakes, cooling, engine, heating, instrument panel, lights and locks.
A security expert said: 'Cars benefit from the fact that they are not connected to the internet and currently are not able to be remotely accessed.
'So in order to carry out a successful attack you would already need to have physical access to the vehicle.'