In a massive end-of-the-year deal, security firm FireEye acquired Mandiant in a deal valued at $1 billion, according to the New York Times. The paper also said the deal came after the two firms started collaborating earlier in 2013 according to VentureBeat.

FireEye's security product works by watching for known and unknown malware. The system utilizes machines to monitor network traffic for strange behavior patterns. If something pops up, the system blocks that certain traffic from coming in, the report explained.

The New York Times said the two companies had been working on projects through their complementary technologies. Mandiant would come in after FireEye discovered something fishy in a network. In addition to taking on cyber criminals, the security firms are also taking advantage of the recent NSA leaks revealed by Edward Snowden, the report detailed.

According to the founders of both firms, their companies are not going to turn to the US for assistance on their system monitoring and security. Instead, FireEye will take advantage of this opportunity to snag new, cautious clients, the report said.

Under the terms of the transaction, Mandiant founder Kevin Mandia will become the chief operating officer of FireEye, VentureBeat reported.