The socio-monetary incentives of online social network malware campaigns

Online social networks (OSNs) offer a rich medium of malware propagation. Unlike other forms of malware, OSN malware campaigns direct users to malicious websites that hijack their accounts, posting malicious messages on their behalf with the intent of luring their friends to the malicious website, thus triggering word-of-mouth infections that cascade through the network compromising thousands of accounts. But how are OSN users lured to click on the malicious links? In this work, we monitor 3.5 million Facebook accounts and explore the role of pure monetary, social, and combined socio-monetary psychological incentives in OSN malware campaigns. Among other findings we see that the majority of the malware campaigns rely on pure social incentives. However, we also observe that malware campaigns using socio-monetary incentives infect more accounts and last longer than campaigns with pure monetary or social incentives. The latter suggests the efficiency of an epidemic tactic surprisingly similar to the mechanism used by biological pathogens to cope with diverse gene pools.