What is IMSI Catcher?

The Legendary Event Of Signal Intelligence

What is IMSI Catcher?


International Mobile Subscriber Identity(IMSI)



It is a unique identity used to identify a user. It is used to prevent
listeners from recognizing and monitoring the subscriber on the radio interface. IMSI is rarely sent
and a temporary mobile subscriber ID (TMSI) randomly generated is sent instead of IMSI. When a mobile
device is connected, a temporary IMSI is allocated and used to identify the subscriber in future
exchange transactions. This is embedded in the mobile equipment SIM. And it is provided whenever the
Network is accessed.


The IMSI Catcher is a tool that can be used to track who is attending
a political demonstration or an event such as a football match. They can even be used to track your
calls and edit your messages.

They have many names; digital analyzer, IMSI catcher, Stingray,
Triggerfish, Dirt Box, Cell-site simulator. It introduces itself to the users as a base station and the
user no longer communicates via the base station, but via this created base station. Isn't that
something you remember? MITM (man-in-the-Middle Attack)




Mobile phones can make or receive calls via radio signals. They can
perform these operations by connecting to the cellular network system offered by the

Phones communicate with base stations via radio frequencies. The base
station is connected to the infrastructure of the operator with copper cablobs. Radio frequencies
spread out to create a certain area. Cell phones within this area are connected to this station. Within
the city, areas that can be spread to ranges of 2-3 km in diameter are formed. Mobile phones are
automatically connected to nearby base stations for minimum power consumption. That's why when a
fake base station is set up, it affects a lot of people in the city.




What data can be collected and what can be done?

  • Geographic location information.
  • Dec (n)direction of Man, Number made Call, Date time of call,
  • duration of call, geographic location information of the call, etc.
  • Fake calling and sending text messages
  • Sending fake text messages by changing geolocation
  • information.
  • Listening to mobile data and entering websites
  • etc.
  • Dos (denial of service) attacks and the interruption of data
  • communications of other mobile phones.


Who uses IMSI catchers?

This tool can be used by ordinary people as well as by police and
senior authorities. It is specially produced. But a simple level can be done at home. Even if the
coverage isn't that good, it still basically works on the same logic. It is a tool often used by
intelligence and police departments.

How can an IMSI catcher find my identity?

IMSI is a number specific to your SIM card. And stands for"
International Mobile Subscriber Identity". Your phone shows this special ID after connecting to an
IMSI catcher. Once the police have your IMSI, they can easily find you.


Can the IMSI catcher review my calls and messages?

Yes. Some IMSI catchers can read your communications. It can interrupt
your calls and internet traffic. Some IMSI Cathers may also block purchases. So you can't even use
your phone to make emergency calls.