The Tricks of the Trade: What Makes Spam Campaigns Successful?

Spam is a profitable business for cyber criminals, with the revenue of a spam campaign that can be in the order of millions of dollars. For this reason, a wealth of research has been performed on understanding how spamming botnets operate, as well as what the economic model behind spam looks like. Running a spamming botnet is a complex task: the spammer needs to manage the infected machines, the spam content being sent, and the email addresses to be targeted, among the rest. In this paper, we try to understand which factors influence the spam delivery process and what characteristics make a spam campaign successful. To this end, we analyzed the data stored on a number of command and control servers of a large spamming botnet, together with the guidelines and suggestions that the botnet creators provide to spammers to improve the performance of their botnet.