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What is IMSI Catcher & How does it work?

IMSI Catcher is the device used by government Agencies for tapping mobile phones. Government agencies have legal permission to do tapping when it comes to national security or the accused person have done something illegal. It is not just government that has the monopoly for using the IMSI-catchers anymore. People can take measures to counter it. 

How do the IMSI catcher work?

IMSI-catchers are the devices that come with the act that like fake cell towers that comes with a trick for target’s devices for connecting with them. The relay for the communication for the actual cell tower of every network carrier. For the target’s communications like calls, text, messages, internet traffic and many more. Forgoing through the IMSI catcher and it can be collected and then read or listened to as per they require it. At the same time, the victim will not have any idea what is happening over the device. Since everything on the device will ultimately look like normal. In the secured field, it is called like man-in-the-middle attack.

 It is entirely possible for having a loophole in the GSM protocol. The mobile phone altogether looks to the tower with the strongest signal, leading to providing the best service. When the device connects to the network, it authenticates the International Mobile Subscriber Identity, but unfortunately, the tower will not show back. For this, the company has to place a building in every location to connect the device and give the IMSI. 


When government agencies do the tracking and all it relates to the devices that remain under the confines of the law. IMSI catchers collect all the data on all phones within a certain radius and even listen to all the calls again. The concern is the government’s actions and what they do with all these records. But as a citizen, and if you are not related to any criminal offence, don’t worry. 


What can you do to protect yourself from IMSI catchers?

If you are present in the range of IMSI catchers, you can feel it. Nothing is in your hand that can stop them. The device will automatically connect to the fake tower. Mobile security companies are getting concerned about this because they are trying to make data incomprehensible for third parties. Thus the agencies can hack if your communication network is wholly encrypted and robust contemporary encryption algorithms like those used for the encrypted communication suite and secure packs. 

Encryption is the first line for the defence sector. The stingrays intercept the IMSIs for the device. The ID number can be easily used to track the location of any device and all about the device owner. Other IMSI catcher models allow to baseband processors of any smartphone directly. This will potentially allow the attackers to subvert encryption by only intercepting communications on the devices. For avoiding all this then you should steer clear for IMSI catchers altogether. 



The IMSI catcher is an instrument used for getting the records of mobile phones. Other agencies other than the government can hack people’s phone records, call logs, and necessary data in this device. After getting to the range of hackers, the person can’t stop anything from happening since the phone will automatically connect to it. 

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