[YesAuto Technology] We often see characters in Hollywood or Hong Kong movies prying a car door or smashing a car window, accurately removing the two wires under the steering wheel and riding on the bridge section of the electric car. Stealing a car is really like in a movie That simple? Today we will talk about how the anti-theft system protects the car.

Is the plot of the movie real?

For the early cars, perhaps the method of sparking wires in the movie is indeed feasible. But with the development of automotive electronic technology, almost all cars today are equipped with electronic anti-theft systems, so those movie plots can no longer be brought into reality.

How does the car perceive the thief?

The car is detected by the door sensor, and the detected information is transmitted to the anti-theft electronic control unit of the car. Once the door is opened illegally, the anti-theft electronic control unit will instruct the actuator to respond accordingly, such as through the horn and the lamp. Sound and light alarms. In addition, in order to prevent the vehicle from being driven away by the thief, the car will automatically control the ignition system and fuel supply system to prevent the engine from starting.

Even on models equipped with a more sophisticated anti-theft system, there are special sensors in the car to detect whether there is activity in the car when the car is locked. Therefore, even if the car thief passes the door, the car will be caught in the car. These sensors sense it and trigger the self-protection program.

Can the car thief break the central control door lock system?

Apart from entering the car by violent methods such as prying the door and smashing the window, can a car thief open the door gracefully by other means? Faced with the more complex remote control central control door lock, hackers may offer a trick to the car thief. Recently, a hacker team formed in Chaoyang District, Beijing, discovered a loophole in the central control door lock system of some auto manufacturers, which can open the car doors normally without violence.

The reason why the above three models were cracked by this hacker team is because these three cars have one thing in common. What vulnerabilities did the hackers catch them? Don't rush to announce, let's first understand the principle of the car's central control door lock system.

●Is our remote control key really so unsafe?

-Principle of central control door lock system

The central control door lock system on early cars used fixed-code verification, that is, the remote control key and the interior door lock system both store the same key to verify each other's identity. Due to the small amount of passwords in this way, repeated codes are prone to appear, so the security is not high. At present, cars basically adopt the code-hopping style with higher safety.

How does the car recognize the different password sent by the key each time?

Each time the owner presses the remote control key, a signal will be sent out, and the key value stored in the key itself will change by adding 1, which is equivalent to changing a new key. When the car receives a signal containing a key value, it will first compare this key value with the key value saved by itself. If the received key value is larger than the key value saved by itself and within a certain range , The car will execute the unlock or lock response, and save the received key value as the benchmark for the next comparison. This means that only the “new key” can unlock or lock the car, thus ensuring the extremely high dynamic security of the key.

When we unintentionally press the remote control key, although the car does not receive a signal, the key value in the remote control key is actually increasing. That is to say, the key itself cannot know whether the door is unlocked and locked. process. For example, when we unlock the vehicle again, the key value issued by the remote control key is already 100 greater than the value stored in the car. At this time, when the owner walks to the front of the car and presses the unlock button, the central control door lock cannot recognize this exceeding its authentication. Range signal, so the door will not be unlocked immediately. The owner usually presses the unlock key again. At this moment, the key value contained in the signal sent by the key and the key value sent last time just meet the conditions of the second verification, so the door Then it was unlocked.

Vulnerabilities in the central control door lock system ignored by automakers

This hopping-code verification method itself has no flaws, and its security is very reliable, but some car manufacturers have exposed problems using this method. Many car companies have adopted the key chip produced by the American Microchip company, and then the purchased chip is matched with the vehicle, and there may be procedural loopholes during the matching.

In addition to the three cars that have been cracked by hackers mentioned above, some models such as Nissan, Toyota, Suzuki, Hyundai, Chevrolet, Haima, Zhonghua, Chery, and Geely all use the American microchip central control door lock chip, so the hacker It is said that if they have the above-mentioned flaws when matching the models of the central control door lock system, they will also face such safety problems.

How can I start the car?

Unlocking the central control door lock system does not mean that the car thief can steal the car. It also requires a key to start the engine. At present, there are three main types of keys for starting the engine. The first is a purely mechanical key; the second is an electronic response key with a remote control module added to the mechanical key; the third is a more popular engine today Keyless start system.

Needless to say, the purely mechanical key is anti-theft by matching the specific tooth profile of the key with the key socket on the car. Insert the key and rotate it to unlock the steering wheel and start the engine. Compared with purely mechanical keys, electronic response keys are more secure and are currently the more mainstream key type.

The keyless start system is becoming more and more common in automobiles. The owner only needs to carry the key on his body, and he can start the car with one button by pressing the button, which greatly improves the convenience of using the car.

You might think of unlocking the keyless start system of the engine by cracking the central control door lock system. Generally speaking, the key of the keyless start system is much more complicated than the key of the central control door lock system, so it is difficult for hackers to start the engine by recording the key signal. However, as more and more cars are currently using the Internet of Vehicles system, there is another channel for hackers to crack the engine system.

●The Internet of Vehicles has become a new hidden danger of the anti-theft system

The automobile part of the vehicle network system can be used to remotely unlock the vehicle, remotely start the engine, and control the air-conditioning, multimedia system and other functions through the mobile phone App. The opening of the car has given the network more control and restriction, so hackers have the possibility of hacking the car anti-theft system through network vulnerabilities to invade the car owner’s car networking account. Regarding the security of the Internet of Vehicles system, we have already published the “Iomotive Internet Is Not Safe?” See how hackers hack a car has been discussed in the article, so I won’t repeat it here.

Edit summary:

It can be said that “the power is high and the magic is high.” Perhaps there are no locks that cannot be unlocked in the world. Some are just through the continuous advancement of technology to improve the safety of cars to the anti-theft system that hackers or car stealers cannot crack at this stage. As mentioned in the article by the hacker team in Chaoyang District, Beijing, the vulnerabilities in the central control door lock system that they discovered have become an important feedback to car manufacturers, which has caused car manufacturers to attach importance to car safety.

For every car owner, as long as we develop a good habit of locking the car, buy car theft insurance, and not put too expensive items in the car, we believe that as the car anti-theft system continues to be updated and improved, the loopholes will be one by one. Be filled. Automobile safety is indeed an issue worthy of our attention, and higher requirements are placed on manufacturers' automobile safety technology. On the other hand, these hackers are also the driving force to promote the development of automotive security technology, which has a certain commonality with the IT industry. In addition, such a process is also the only way to go through the electronicization of automobiles. Finally, here is a suggestion to the movie screenwriters, do not write out the bridge section that can start the car with the wire in the future. (Auto House Text/Picture Xia Zhimeng)