Inside the SCAM Jungle: A Closer Look at 419 Scam Email Operations

Nigerian scam is a popular form of fraud in which the fraudster tricks the victim into paying a certain amount of money under the promise of a future, larger payoff. Using a public dataset, in this paper we study how these forms of scam campaigns are organized and evolve over time. In particular, we discuss the role of phone numbers as important identifiers to group messages together and depict the way scammers operate their campaigns. In fact, since the victim has to be able to contact the criminal, both email addresses and phone numbers need to be authentic and they are often unchanged and re-used for a long period of time. We also present in details several examples of Nigerian scam campaigns, some of which last for several years - representing them in a graphical way and discussing their characteristics.