TAG | gsm
0 Comments | Posted by Hendrik Schmidt
After a couple of years in pentesting Telco Networks, I’d like to give you some insight into our pentesting methodology and setup we are using for testing “Mobile and Telecommunication Devices”. I am not talking about pentesting professional providers’ equipment (as in previous blogposts), it is about pentesting of devices that have a modem in place like a lot of IoT devices (you know about the fridge having a GSM Modem, right?) do.
only a few seconds left! As a short reminder, there is a GSM network running on Troopers 2016. It should be available in the whole building. To attend the network you need to
- Get a SIM Card @Troopers_Desk
- Put it in your phone
- Start the phone
You can always dial *#100# to get your phone number. All further information (and a phonebook) you’ll find on gsm.troopers.de, but here again a brief summary:
- Update your name in phonebook via sending your_name to 1000
- Submit tokens via sending your_token to 1111 (you must register at the terminal first)
Please note, against to our announcement, there is not Internet (GPRS) yet. Due to questions and problems, please contact Kevin Redon or Hendrik Schmidt. Have fun!
Same as last year, we will have a GSM based telephony network running at Troopers 2016. The network will be a closed network, which means it only can be used with Troopers SIM cards and between Troopers attendees only. You can use the network for
- doing Voice Calls
- send Short Messages (SMS)
- have Internet Access
- submit Challenge Tokens (see below)
While running some SS7 pentests last year, I developed a small tool automating some of the well-known SS7 attack cases. Today I’m releasing the first version of ss7MAPer, a SS7 MAP (pen-)testing toolkit.
In our talks in the past we showed what might be possible if an attacker gets access to backhaul and/or core network of a telecommunication provider. In a security analysts perspective this is really disgusting, but provider always will argument that those attack scenarios are not realistic.
Additionally to Wifi, Troopers is also offering a GSM network.
If you want to use it, simply ask your phone to scan for available mobile networks. There you should see the usual T-Mobile D, Vodafone.de, E-Plus, O2-de operators, but also the unusual D 23 or 262 23. Just select this one, and your are done. You also can use the Troopers SIMs which you get on the welcome desk on the ground floor.
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 😀