MALWARE INFECTION PREDICTION

A computer implemented method of protecting a target subnet, including a set of network connected devices in a hierarchy of subnets of a computer network, from malware attack. The method includes generating a dynamical system for each subnet in the network, each dynamical system modelling a rate of change of a number of network connected devices in the subnet that are: susceptible to infection by the malware; infected by the malware; protected against infection by the malware; and remediated of infection by the malware. The dynamical systems are based on rates of transmission of the malware between pairs of subnets; evaluating a measure of risk of infection of the target subnet at a predetermined point in time based on the dynamical system for the target subnet; and responsive to the measure of risk meeting a predetermined threshold, deploying malware protection measures to devices in the target subnet.