In some Eastern European countries (Russia and Ukraine especially), there are legal loopholes that allow the use of SMS premium rate numbers anonymously. In addition, some Russian mobile operators allow people to transfer money from prepaid SIM cards to bank accounts or credit cards. When combined, these two things allow cyber-crime activity that generate illegal profits. In this issue of Lab Matters webcast, Kaspersky Lab malware researcher Denis Maslennikov discusses this component of mobile security and talks about the ways cyber-criminals are maliciously exploiting prepaid SIM cards and money transfers. Maslennikov also describes the main pillar of the underground economy and ecosystem of his type of fraud.