In one embodiment, a security device in a computer network detects potential domain generation algorithm (DGA) searching activity using a domain name service (DNS) model to detect abnormally high DNS requests made by a host attempting to locate a command and control (C&C) server in the computer network. The server device also detects potential DGA communications activity based on applying a hostname-based classifier for DGA domains associated with any server internet protocol (IP) address in a data stream from the host. The security device may then correlate the potential DGA searching activity with the potential DGA communications activity, and identifies DGA performing malware based on the correlating, accordingly.