Chris Woodyard

USA TODAY

The FBI and the National Highway Traffic Safety Administration are jointly warning that modern cars are vulnerable to hacking.

That may come as no surprise to those who have followed news reports about the possibility, but it does show the level of attention coming to the issue from the nation's top federal law-enforcement agency. The FBI's "public service announcement," issued Thursday, cites recent demonstrations in which researchers showed how they could remotely take over various functions in cars.

"The analysis demonstrated the researchers could gain significant control over vehicle functions remotely by exploiting wireless communications vulnerabilities," the warning reads, adding that "consumers and manufacturers are aware of the possible threats and how an attacker may seek to remotely exploit vulnerabilities in the future."

The memo points to the many different computers contained in today's cars that control functions ranging from braking to infotainment. Each has their own set of vulnerabilities, especially when it comes to the possibility that the systems can be manipulated by plugging a laptop or other device into the car's diagnostic port. Over the summer, a team from Wired magazine managed to hack into a Jeep Cherokee SUV and drive it into a ditch.

Attacks can also occur via Wi-Fi, usually at no more than 100 feet from the vehicle. A car traveling at low speeds can be vulnerable to having its engine shut down, brakes disabled or interference with the steering. For cars traveling at higher speeds, hackers can fool with the door locks, turn signal, tachometer, radio, air conditioning or GPS.

The warning cites a July recall of 1.4 million Ram, Jeep, Chrysler and Dodge vehicles that were susceptible to hacking through their infotainment systems, following the demonstration by Wired. Owners were being sent a thumb drive with a software patch to remedy the problem.