IMSI Catcher

Thanks to Keld Norman

Here is the guide to create the IMSI catcher with a cheap SDR dongle:

1. Install Ubuntu 16.04.2 LTS Go to http://releases.ubuntu.com/16.04/ and download the Ubuntu 16.04 LTS version of a 64bit desktop.

Here is the direct link that worked when i wrote this guide: http://releases.ubuntu.com/16.04/ubun…

If you use a VM then give it a min. of 2Gb Memory. Compiling might crash if there is not enough memory I gave my VM 1 cpu, 2G memory, 20Gb disk, removed the printer and sound card and left the USB in usb2.0 mode.

Update ubuntu after the installation is done: sudo apt-get update && sudo apt-get upgrade -y reboot

1. Install GNU Radio GSM modules / gr-gsm sudo apt-get install git python-pip sudo pip install PyBOMBS sudo pybombs prefix init /usr/local -a default_prx sudo pybombs config default_prefix default_prx sudo pybombs recipes add gr-recipes git+https://github.com/gnuradio/gr-recipe… sudo pybombs recipes add gr-etcetera git+https://github.com/gnuradio/gr-etcete… sudo pybombs install gr-gsm # This one could take hours to complete sudo ldconfig

• Plug in the SDR-Dongle and check it is detected with dmesg. Then test if gr-gsm works: sudo grgsm_livemon # You should see the blue signal fluctuate

• If you see this error - you forgot sudo in front of grgsm_livemon
• Using device #0 Generic RTL2832U OEM
• usb_open error -3
• Please fix the device permissions, e.g. by installing the udev rules file rtl-sdr.rules
• FATAL: Failed to open rtlsdr device.

1. Get the python script to grap the data and present them nicely:
   • Install the pre reqs. sudo apt install python-numpy python-scipy python-scapy

• Get the scripts git clone https://github.com/Oros42/IMSI-catche…

• Update the network providers list python IMSI-catcher/mcc-mnc/update_codes.py

# In terminal 1 cd IMSI-catcher sudo python simple_IMSI-catcher.py

# In terminal 2 Start the radio wave sniffer on a channel where a GSM base station/tower transmits in your area. #—————– airprobe_rtlsdr.py -f 943400000 # this is the same program called grgsm_livemon

Now, change the frequency and stop it when you have output like in the console behind the gui:
4c 69 6b 65 56 69 64 65 6f 3d 53 65 6e 64 63 68 6f 63 6f 6c 61 74 65
00 6b 65 6c 64 2e 6e 6f 72 6d 61 6e 40 67 6d 61 69 6c 2e 63 6f 6d 00 Watch terminal 1 and wait. The TMSI/IMSI numbers should appear shortly

If nothing appears after 1 min, change the frequency.

You can also watch the GSM packets in wireshark like this: sudo apt-get install -y wireshark tshark # NB: tshark is a commandline version of wireshark sudo wireshark -k -Y ‘!icmp && gsmtap’ -i lo # ignore errors about not running wireshark as root..