System and method for monitoring security attack chains

A cybersecurity platform is described that processes collected data using a data model to identify and link anomalies and in order to identify generate security events and intrusions. The platform generates graph data structures using the security anomalies extended using additional data. The graph data structures represent links between nodes, the links being events, the nodes being machines and user accounts. The platform processes the graph data structures by combining similar nodes or grouping security events with common features to behaviour indicative of a single or multiple security events to identify chains of events which together represent an attack.