His research interests lie in the area of computer security and he is particularly interested in browser security and building systems that solve security problems. In the past, he was the lead developer of Wepawet, a system that detects drive-by downloads with the use of an emulated browser, Hulk, the first system that automatically identifies malicious browser extensions, and Revolver, a system that detects evasive drive-by download attempts. He is currently interested in internet-wide attacks, building scalable systems to protect users and improving privacy on the web.