DEV Community

Cover image for What are IMSI Catchers and how to evade them

Posted on

What are IMSI Catchers and how to evade them

International mobile subscriber identity or IMSI was originally from the time when cellular networks needed to know when you were on their towers and when you were roaming. The IMSI code uniquely identifies the mobile network operator, and identifies your mobile phone to that network operator.

IMSI Catchers
Alt Text

IMSI catchers or stingrays work by acting as fake cell phone towers.
Cell phones can connect to these IMSI catchers instead of legitimate towers and all calls, data, and SMS messages can be monitored, intercepted and manipulated.

Have you ever been to Super Market and you get a personalized greeting like "Hello Umegbewe". We haven't met anywhere and I haven't never been to that supermarket, never!! 😲

How???? 🧐

When you enter the store or supermarket, an IMSI catcher grabs information from your cellphone and gets the IMSI, then do some queries to databases and tada tada 💃 it gets your profile like your Full name, Phone number, DOB, mother's maiden name etc. All these happen in a blink of a eye, without a warning!!! Your privacy was intruded 😌 But it doesn't end there 🥵 because calls and sms could be intercepted and monitored.
Now, you get why is easy for the government to identify Individuals who are at a rally or protest with IMSI Catchers without facial recognition they can even get evidence of a protester calling others at home to join the protest, you know the government they can use the slightest of things against you.

How to evade IMSI Catchers??

There are several ways to evade IMSI Catchers but it needs a bit of technical ability.

  1. AIMSICD - Android IMSI-Catcher Detector is an open-source-based Android app to detect and avoid IMSI Catchers or other base-stations (mobile antennas) with poor or no encryption. This solution also warns users if the connection ciphering is turned off, and when their phones are being subject to hidden tracking via Silent/Stealth (Type-0) SMS. AIMSICD also enables several other protection-mechanisms to safeguard you from IMSI and other types of mobile network attacks.
    AIMSICD also includes a real-time network security status indicator and a map-based security overview of the mobile network area.

  2. SnoopSnitch adopts a different approach to combat IMSI Catchers. It analyzes your phone’s firmware for installed or missing Android security patches (even on rooted devices). SnoopSnitch can also collect and analyze mobile radio data to make you aware of your mobile network security and to warn you about threats like IMSI catchers and user tracking.
    SnoopSnitch is a community app. Patch analysis results and firmware build details are uploaded to its server to enable improvements and upgrades.

*Note: The Government and few organizations are getting cunning this days, and develop more sophisticated IMSI Catchers, we now depend on Open Source lovers to counter this mobile surveillance. You don't have any privacy so get over it.

Discussion (1)

abbeymaniak profile image

Nice thread