Abstract: A computer system comprises a machine-learning (ML) system at which alerts are received from endpoints, wherein the ML system is configured to: upon receiving a first alert and a second alert, apply an ML model to the first and second alerts; based at least in part on the first alert being determined to belong to a first cluster of the ML system, classify the first alert into one of a plurality of alert groups, wherein alerts classified into a first alert group of the alert groups are assigned a higher priority for security risk evaluation than alerts classified into a second alert group of the alert groups; and based on the second alert being determined to not belong to any cluster of the ML system, analyze a chain of events that triggered the second alert to determine whether there is suspicious activity associated with the second alert.