(Cross posted from http://www.simionovich.com/2017/01/08/telephony-fraud-still-going-strong/)
Who would believe, in the age of Skype, Whatsapp and Facebook – telephony fraud, one of the most lucrative and cleanest form of theft – is still going strong. Applications of the social nature are believed to be harming the world wide carrier market – and carrier are surely complaining to regulators – and for a legitimate reason. But having said that, looking at some alarming fraud attempt statistics, thing will show you a fairly different story.
So, analysing fraud is one of my things, I enjoy dropping honeypots around the world, let them live for a few days and then collect my data. My rig is fairly simplistic:
- A have a Homer (www.sipcapture.org) server to capture all my traffic
- A have an amazon AWS cloudformation script that launches up instances of Asterisk, FreeSwitch and Kamailio
- All instances are pre-configured to report anything back to Homer
- Upon receiving a call – it will be rejected with a 403
Why is this a good honeypot scheme? simple – it gives the remote bot a response from the server, making it keep on hitting it with different combinations. In order to make the analysis juicy, I’ve decided to concentrate on the time period between 24.12.2016 till 25.12.2016 – in other words, Christmas.
I have to admit, the results were fairly surprising:
- A total of 2000 attacks were registered on the honeypot server
- The 2 dominant fraud destinations were: The palestinian authority and the UK
- All attacks originated from only 5 distinct IP numbers
Are you wondering what the actual numbers are? Here is the summary:
|Row Labels||126.96.36.199||188.8.131.52||184.108.40.206||220.127.116.11||18.104.22.168||Grand Total|
As you can see, the number 972592315527 was dialed 1774 times from a single IP – 22.214.171.124. I can only assume this is a botnet of some sort, but the mix of IP numbers intrigued me. So, a fast analysis revealed the following:
Amsterdam? I wonder if it’s a coffee shop or something. The thing that also intrigued me was the phone number, why would the bot continue hitting the same mobile phone number? I couldn’t find any documentation of this number anywhere. Also, the 97259 prefix automatically suggests a mobile number in the PA, so my only conclusion would be that this is a bot looking for a “IPRN” loop hole – which is again fraudulent.
So, if this what happens in 48 hours – you can imagine what happens over a month or a year.