An Example—Dissecting a Spam Network

Now let’s see how these tools can be used in the real world. This section shows how you can figure out the structure of a sophisticated spam operation. A point that I will stress here and throughout the book is how valuable it can be to have multiple examples of an email or a web site. Even though the details may differ, the similarities between them can be very revealing.

For a while last year I was getting a lot of spam emails that all had a similar underlying appearance. The products being offered varied, as did the name of the Sender, but they clearly had a common origin. The From addresses all had the form and they all had the same mechanism for unsubscribing from their mailing list. So I collected a bunch of messages that fit this pattern and made a list of the web sites they were directing me to. At first glance these seemed to be a diverse group but as I added more examples the domain names started to take on a similar form. That was my motivation to investigate further and start to run dig on the hostnames. Table 2-3 shows a small sample of the results from that survey, sorted by IP address.

Table 2-3. Hostnames with similar IP addresses

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