Bitcoin's 'been a problem for us,' says CEO of top cybersecurity firm FireEye By: CNBC.com News May 04, 2018 at 18:48 PM EDT Jim Cramer hears from Kevin Mandia, the CEO of FireEye, about the risks that cryptocurrencies pose to cybersecurity. Read More >> Related Stocks: Bitcoin (Bitstamp) Bitcoin Composite Cnooc Ltd Fireeye Inc