A niche term just two years ago, ransomware has rapidly risen to fame in the last year, infecting hundreds of thousands of users, locking their documents, and demanding hefty ransoms to get them back. In doing so, it has become one of the largest cybercrime revenue sources, with heavy reliance on Bitcoins and Tor to confound the money trail.

In this talk, we demonstrate a method to track the ransomware ecosystem at scale, from distribution sites to the cash-out points. By processing 100k+ samples, we shed light on the economics and infrastructure of the largest families, and we provide insight on their revenue and conversion rates. With a deep dive in the two largest groups, we show the details of their operation. Finally, we uncover the cash-out points, tracking how the money exits the bitcoin network, enabling the authorities to pick up the money trail using conventional financial tracing means.