A device and method for providing forensic data in network activity indicative of the presence of malware. A distributed set of network-based sensors operates within an enterprise network in cooperation with a centralized analytics and correlation engine that correlates detected events across the sensors to detect malicious activity on a monitored network which may include using a multi-tiered or Rete net rule set or engine. When malicious activity is detected upon the satisfaction of a predetermined set of conditions, the invention traces the activity to a host responsible for the activity for further action.