TAG | a5/1
Finally it’s here!
pytacle is a tool inspired by tentacle. It automates the task of sniffing GSM frames of the air, extracting the key exchange, feeding kraken with the key material and finally decode/decrypt the voice data. All You need is a USRP (or similar) to capture the GSM band and a kraken instance with the berlin tables (only about 2TB )
I’ve posted a preview before, take a look at the video to see the tool in action.
The tool is early alpha, so it’s working (for me ), but it’s neither rock stable nor packaged in any way. But still, I’ll be happy to get bug reports.
BTW, talking about Telco security: There will be another TelcoSecDay on 03/12/2013 at next year’s Troopers! We’ve already some quite interesting talks confirmed.
today I’ll give a short preview of my newest tool, pytacle. It is simply a little helper program to control gnuradio/airprobe/kraken/some_other_tools, convert their input/output and to find a use able clear/cipher text combination to break A5/1. In the end it should record, crack and decode/play a gsm phone call with ~5 mouse clicks.
Take a look at this video:
The code is not available yet, as its not finished the recording and cracking part are working, but the decoding doesn’t. I need to put some more time into the code, but there isn’t much spare in that time of the year