Recently, a video that “successfully open the smart lock in just 3 seconds” has been circulated on the Internet, making countless smart lock merchants and many consumers look dumbfounded. In the video, the person holding the small black box and shaking it in front of the smart lock a few times, the smart lock is easily opened, as if taking a door card

3 seconds to open the lock, small black box broken lock tool

There is no time-consuming and laborious violent unlocking, and there is no complicated and high-end technical cracking. No matter how complex smart locks are swiped in the air, they can be easily opened. Just use the following little black box that looks bad. It is a little smaller than a mobile phone, but twice as thick, and a copper coil is exposed on the top of the box.

Small black box

The small black box transmitted on the Internet is actually a Tesla coil. The structure of the small black box is not complicated. It is a Tesla coil—a device that uses a transformer to boost an ordinary voltage and then discharges from the discharge terminal through a two-stage coil; In layman’s terms, it is an artificial lightning maker.

We all know that the Tesla coil generates strong electromagnetic pulses. If you put it close to a fluorescent tube, the tube will light up. And this kind of high-frequency, high-intensity electromagnetic pulse can damage the surrounding electronic equipment.

The pulse generated by the small black box can make the bulb emit bright light when there is no power supply

There are only two buttons on the small black box, the bottom is the power button, and the side is the trigger switch. Put the copper coil of the black box close to the smart lock, walk around in different positions of the lock body, and press the trigger button one at a time. After a few seconds, the smart lock with the fingerprint and password originally set is opened!

Small black box test smart door lock

Vulnerability in the input signal of the smart lock motor

“The voltage stabilizer and current overload protection are used to optimize and protect the power system. When we use the coil to unlock, we can hear the voice announcement:’Already open’, which shows that the overall function of the smart lock, including the power supply, is normal The coil pulse does not damage the power system, so it can be pushed out and has nothing to do with the voltage stabilizer.” All, it is likely that the pulse interference of the small black box generates current, which passes through the internal components of the smart lock to generate a signal that makes the system Misunderstood that it was a normal command and triggered the motor start. ”

To verify this conjecture, we disassembled a smart lock and unplugged the power supply inside. When the small black box approached the circuit board again, a magical thing happened——

Obviously there is no power supply, but there is voltage response on the universal meter. Then plug in the power and use the small black box to attack the test again. At this time, the lock is unlocked! That is to say, under the interference of electromagnetic waves, a current appears. The current is like a signal flare, triggering the motor drive chip, and the lock is unlocked.

Can the Guub fingerprint lock be opened in seconds?

In this regard, Guub Technology, a manufacturer of secure cabinets and smart locks that is popular in the market, attaches great importance to this. Guub engineers conducted a detailed investigation on this phenomenon at the first time, and the latest Z168 series of fingerprint locks developed by guub in 2018 The safe was tested in practice.

In the test video, the Z168 fingerprint lock cannot be illegally cracked and unlocked as described on the Internet, and there is no need to worry about its security.

Although the Tesla coil (small black box) transmitted online cannot open the guub Z168 series fingerprint lock safe, the small black box is indeed effective for opening ordinary smart locks on the market.

Therefore, I would like to remind everyone: Be careful when buying smart locks and fingerprint lock safes, and be sure to buy trusted products from big brands.