“The short answer is they sell it on the cyber criminals’ black market. According to a report released earlier this year by the RAND Corporation’s National Security and Research Division, the hacker market is highly sophisticated and organized. The hacker market has, in some respects, become more profitable than the illegal drug trade, that report found. The data hackers steal ends up on a network of illegal trading sites where they buy and sell large amounts of personal data for profit. “
Source:Hackers Are Selling Your Data In Highly Sophisticated Black Markets – Business Insider