Passive IMSI Catching On A Real GSM Network Using A RTL-SDR And Gr-GSM

Recently, I had the opportunity to play around with a real 2G cellular network. So, here is a quick video of how passive IMSI catchers are constructed using a couple of Linux software tools and an RTL-SDR dongle.

It is a common misconception that mobile phones are tracked via their telephone numbers or the IMEI number of the handset. IMSI is an abbreviation that stands for 'international mobile subscriber identity' and is the unique identifier of a mobile phone subscribers SIM card on a cellular network. IMSI numbers are used in most mobile phone communication generations from 2G, all the way up until the more modern 5G.

The IMSI number of a SIM card is very well protected in 3G, 4G and 5G. However, in the case of the 2G mobile communication standard GSM, these unique identifying values are not so well protected from the prying eyes of governments, militaries, law enforcement and spy agencies.

#SDR #IMSI #ImsiCatcher #GSM #Cellular

GSM Voice Decryption From Start To Finish (2G Non-Hopping Only)

The GSM data used in the making of this video was recorded and decrypted with unanimous consent from the owner(s) for the purpose of demonstrating the 2G decoding features of gr-gsm and for evaluating cellular network security.

Due to it's complexity and difficulty, decoding 2G phone calls is considered by most to be the hardest task to accomplish in the realm of GSM decoding. Differing voice codecs, varying channel data rates, arbitrary allocation of frequency hopping and carrier-specific network configurations add too many variables into the mix to make it a straight-forward enough goal to achieve.

I showcase the entire 2G voice decryption process from start to finish, excluding the actual recording of the GSM data

This video was made for purposes of education & experimentation only #IMSI-CATCHING, #SMS-SNIFFING and voice call #interceptior on #CELLULAR #NETWORKS is illegal & punishable by hefty fines & imprisonment

#GSM #2G #SDR #GRsdm