Vehicles manufactured today consist of components called Electronic Control Units (ECUs) which are assigned to different features. A typical car may contain respective ECUs for door control, brake control, and battery management, among almost a hundred other such units. These Electronic Control Units are embedded with software and networked to communicate with one another in various configurations which contributes to the complexity and sophistication of modern vehicular design. 

Some of the ECUs are connected to other ECU units inside the vehicle as well as an external network. The ECUs connected to an external network are typically those that have to do with GPS navigation, Wi-Fi capabilities, or BlueTooth connectivity. These ECUs create the conditions that make it possible for a car to be hacked from an external source. Depending on how the network of ECUs is configured in a car, an attacker could potentially breach a feature such as a car’s built-in Wi-Fi capabilities and extend his control to critical aspects of the car’s infrastructure such as braking or acceleration. 

PT&C|LWG, a forensic consulting firm, has compiled published research, vehicle recall information and media reports to identify “The Most Hackable Cars on the Road.” The cars identified include the 2014 Infiniti Q50, 2015 Cadillac Escalade, and the 2014 Jeep Cherokee. The latter car experienced a massive recall as a result of a story published in Wired, which saw hackers remotely stop the car in the middle of the highway. Chrysler subsequently recalled 1.4 million vehicles with the identified vulnerabilities. As an example of how hackers could successively control a vehicle by controlling a network of ECUs, before completely disabling the car, “the vents in the Jeep Cherokee started blasting cold air at the maximum setting, chilling the sweat on my back through the in-seat climate control system. Next the radio switched to the local hip hop station and began blaring Skee-lo at full volume...Then the windshield wipers turned on, and wiper fluid blurred the glass.” For a full list of cars affected, see the infographic here.