IMSI catcher detection - Catcher Catcher

Some time ago I wrote a short summary based about recent projects, news about interception and tracking of mobile phones. We should live in the world where every single one phone interception is approved by local jurisdiction, but in a matter of fact that's not really true. Every, even tiny country DO NOT have their own active or passive GSM Interceptor Or let's say deciphering the GSM system. There are many reasons for that and believe me, some of them are pretty reasonable. On the other side, there are many individuals and companies with great desire for private information ... Anyway Whether you want to learn something about GSM or just verify your paranoid Suspicions, Catcher Catcher (OsmocomBB) is what you are looking for.
There are some indicators (location rejects, silent call send at highest power, unencrypted transactions) That your cell phone is being tracked or Intercepted and this is the whole point of this nice project. IMSI catcher detector, lead by Luca Melette (Security Research Labs) is available only for the OsmocomBB platform.
IMSI catcher detection
- Taken from Catcher Catcher Wiki

Catcher Catcher distinguish between yellow, red, and black flags. Yellow flag are an indication That you might have been caught, red flags are a very strong indication, and black flags tell you: "You are being tracked down, throw away your phone and run."

I will skip installation instruction, since that's been cleared in the Osmocom + Catcher Catcher tutorial. Lets connect our Motorola C118 and fire up this great software:

1 root @ bt: ~ / catchercatcher / osmocom-bb / src #. / host / osmocon / osmocon c123xor-m-p / dev/ttyUSB0 ./target/firmware/board/compal_e88/layer1.compalram.bin
2 root @ bt: ~ / catchercatcher/osmocom-bb/src/host/layer23/src/mobile #. / mobile
3 telnet 127.0.0.1 4247

Long story short, let's play a little! First we used "clean" phone - the one we know is not Intercepted. This was just quick test, but as you can see A5 / 1 stream cipher is used, no IMSI / IMEI requrests but silent SMS ...
-> Status flag: Yellow

Second, we used cell phone we know that is being "Intercepted" around some areas> :) Yay! A5 / 0 = no encryption at all. Guess I   you know what this means.
-> Status flag: Red

Will update this article when I see Status flag: black There are much much more options to play with, But that is beyond the scope of this article. For recent updates about setup, flags and progress visit Catcher's Wiki . Please remember this is a work in progress project.