On October 19, 2021, a resident in Jinan found a strange scene when checking the surveillance video in front of his home, only to see a woman wearing a mask approaching the door of his house, and then pulled out something similar to "tape", what did she want to do? It turned out that she used this thing to paste several times at the verification of the fingerprint lock, wanting to "fork" the fingerprint password of the owner of the house!
Apparently, it was a thief who had entered the cell and was using a sticker sleeve while taking fingerprints. So, is there really a loophole in the fingerprint lock? Can the sticker really open the fingerprint lock after removing the fingerprint? What is the recognition mechanism of fingerprint lock? In addition to being easily stolen, what dilemma does it face?
Thieves open locks in a variety of ways
With the development of the Internet, smart homes began to rise, in order to solve the problem of always forgetting to bring the key when going out, smart door locks appeared. Many people have removed their old door locks and replaced them with smart door locks, no longer having to worry about the key not being brought.
However, at the same time, the fingerprint lock seems to have hidden dangers, and many thieves try to use this loophole to steal property.
For example, the thief behavior found by this resident in Jinan through the monitoring in front of the door, this strangely behaved woman is obviously using a sticker to extract the fingerprint of the resident, and then find an opportunity to steal, so can this way of stealing fingerprints open the fingerprint lock?
Generally speaking, after the thief uses the sticker sleeve to steal the fingerprint, he will go back to the "forged fingerprint film", which is sometimes called silicone fingerprint film forgery technology. The thief will subsequently obtain the fingerprint film of the homeowner by rubbing the reverse mold, and then open the door.
This method is currently the most popular use of thieves, because the fingerprint pattern of this fingerprint film is clear and relatively complete, and although it is not completely consistent with the fingerprint of the homeowner, the degree of similarity is already very high.
This method is very threatening for the traditional fingerprint lock that uses optical recognition, because this fingerprint recognition technology will only "extract the image", and it cannot be detected for whether it is a real finger. So the thief can easily use the mold and easily unlock the lock.
In addition to using the sticker sleeve to extract fingerprints, they have developed several other methods to break the "fingerprint lock" and steal. The first is the fingerprint image film making method, which is simply to obtain a high-quality fingerprint image, and then use the relevant optimization "one to one" perfect reproduction of the fingerprint, the cost and technical difficulty of this method are higher than the self-adhesive sleeve inverted mold method, so the "low-level thief" generally cannot do it.
However, there are still more ambitious thieves who will step on them in advance, understand the economic situation of the homeowner's family, and then plan to steal. Everyone knows an old saying called "don't be afraid of thieves, be afraid of thieves", if thieves really use such advanced technology, it means that the owner's property must be enough for him to make a fortune.
Finally, there is an attack on the fingerprint lock system, which is different from the above-mentioned traditional way of stealing fingerprints, but directly from the fingerprint lock system, which can be regarded as a "dimensionality reduction strike". Specifically, it is to attack the vulnerability of the fingerprint recognition system at the computer level, and you can also disguise the electronic signal and bypass the world system to directly issue a unlock signal, which is equivalent to shouting "sesame door" directly in front of other people's doors, which is very scary.
It can be seen that there are indeed some loopholes in the fingerprint lock, and as a product that has not been applied to the market for a long time, it is still immature in many aspects. This can be seen from the frequent fingerprint lock security incidents on the Internet, it is worth mentioning that the Consumer Association in Tianjin paid attention to this situation, and in August 2019, it specially compared 38 smart door locks to test their security performance.
The results show:
Among the 38 smart door lock products, 8 samples had abnormal reactions in the electromagnetic compatibility test... 32 samples can be used to make a "fake fingerprint" unlock, 14 smart door lock samples advertised that there is a living fingerprint function, the actual measurement does not have this function, there is a suspicion of false standards, the proportion of false labels is as high as 36.8%.
Presumably seeing this, some people with smart door locks in their homes can't help but pinch a cold sweat. So, what is the recognition mechanism of smart door locks like fingerprint locks? Are all fingerprint locks on the market the same? Next, let's talk about its three mainstream recognition technologies, which recognition mechanism fingerprint lock is more secure.
Fingerprint lock recognition mechanism
The first is the main target of the fingerprint method of self-adhesive sleeve, the traditional optical fingerprint recognition lock. As we said above, this recognition technology is only responsible for extracting images, and it does not care whether it is really "finger". Because the optical fingerprint recognition mechanism is the earliest and most widely used at present, thieves should "love" this one among many fingerprint locks, after all, the theft rate of unlocking is extremely high.
The basic working principle of the optical fingerprint lock is this, its reflective system will reflect the fingerprint image to the CCD imaging system, and then the system will convert the fingerprint image into a flat digital image, and finally the DPS signal processing circuit will generate a complete array of digits. It can be seen that it is concerned about the similarity of fingerprints, so the fingerprint forged by the self-adhesive sleeve can meet its work needs.
The second is the capacitive fingerprint recognition system, which divides the surface of the semiconductor chip into many pieces, and the fingerprint extraction will be more detailed. Therefore, this fingerprint lock not only requires a fingerprint with a high degree of similarity, but also senses the strength of the capacitive signal at the time of entry, and it is difficult to be opened if it is inconsistent. This fingerprint lock will be safer than the optical fingerprint lock, but the disadvantage is that it is easy to produce static interference, if there are water molecules on the hand, then it will not be recognized.
Finally, there is the ultrasonic fingerprint recognition lock, which is the highest security factor of all fingerprint locks at present, of course, its price is also very high. This fingerprint lock will use the sensor to send ultrasonic waves towards the fingerprint surface, and then based on the principle of pulse echo, using skin and air density to construct a 3D image by itself, the successful recognition rate is as high as 99%.
The reason why it is so safe is because ultrasonic waves can go deep into the fingerprint surface to obtain deep fingerprint lines, so the "surface fingerprint" obtained by thieves using stickers does not work.
It can be seen that the working principle and security performance of the fingerprint lock of the three different mechanisms are more obvious. Everyone needs to pay special attention to which one it is when choosing a fingerprint lock, just as the above consumer association survey results, the fingerprint lock products in the market today are uneven, if you do not carefully screen before purchasing, it is likely to "step on the thunder".
It is worth mentioning that in addition to facing the situation that fingerprint locks are easy to be stolen by thieves, fingerprint locks are also facing some other dilemmas, do you know what they are?
What other dilemmas does fingerprint lock face?
On December 22, 2019, a serious fire broke out in the Jiangnan Coast Garden in Zhongshan Ancient Town, Guangdong Province, resulting in the death of a family of six in B1 duplex house. Later, after investigation, it was found that the cause of the fire was caused by a fire left in the garden location of the home, but some neighbors pointed out that it was because of the problem of "fingerprint lock".
In fact, this statement is not unfounded, if the fire is too fierce, it will make the circuit board of the fingerprint lock burned out, and it is already difficult to open the door from the outside at this time. However, experts believe that this still needs to be discussed according to the specific category of fingerprint locks, because the current fingerprint locks are pure electronic locks, and some are locks where the motor and the lock body are separated.
Experts say:
General mechanical and electrical separation part is in the indoor side, this side of the room with emergency escape function, if it is encountered with open flame combustion, the electronic part loses its function, we can pass the mechanical part, so that we can open the door, out from the inside, this is an emergency escape function.
But when disaster strikes, do panicked people really have time to pay attention to this? Although people are more speculative about the influencing factors of fingerprint locks, it is undeniable that there is indeed some kind of security risk in this lock.
Although the development of science and technology has changed our lives, the problems that come with it also need to arouse everyone's vigilance. Whether it is a threat of theft or a fire hazard, it is best to "prevent problems before they occur".