Telephony Fraud – Further Analysis

Following yesterday’s post, I’ve decided to take another set of data – this time following the start of the year, with a specific data profile. What is the profile? I will describe:

  1. The honeypot server in this case was a publically accessible Kamailio server
  2. The honeypot changed its location and IP every 48 hours, over a period of 2 weeks
  3. The honeypot was always located in the same Amazon AWS region – in this case N.California
  4. All calls were replied to with a 200 OK, followed by a playback from an Asterisk server

In this specific case, I wasn’t really interested in the attempted numbers, I was more interested to figure out where attacks are coming from. The results were fairly surprising:

The above table shows a list of attacking IP numbers, the number of attempts from each IP number – and the origin country. For some weird reason, 97% of potential attacks originated in Western Europe. In past years, most of the attempts were located in Eastern European countries and the Far-East, but now this is Mainland Europe (Germany, France, Great Britain).

Can we extrapolate from it a viable security recommendation? absolutely not, it doesn’t mean anything specific – but it could mean one of the following:

  1. The number of hijacked PBX systems in mainland Europe is growing?
  2. The number of hijacked Generic services in mainland Europe is growing?
  3. European VoIP PBX integrators are doing a lousy job at securing their PBX systems?
  4. European VPS providers pay less attention to security matters?

If you pay attention to the attempts originating in France, you would notice a highly similar IP range – down right to the final Class-C network, that is no coincidence, that is negligence.

Now, let’s dig deeper into France and see where they are attempting to dial:

So, on the face of it, these guys are trying to call the US. I wonder what are these numbers for?

Ok, that’s verizon… let’s dig deeper…

Global Crossing? that is interesting… What else is in there???

 

So, all these attempts go to Landlines – which means, these attempts are being dialed most probably into another hijacked system – in order to validate success of finding a newly hijacked system.

Well, if you can give me a different explanation – I’m all open for it. Also, if any of the above carriers are reading this, I suggest you investigate these numbers.

 

 

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