Abstract: A computer network penetration test discovers vulnerabilities in the network using a number of scan modules. The scan modules perform their scanning of the network separately but in parallel. A scan engine controller oversees the data fed to and received from the scan modules, and controls the sharing of information among the modules according to data records and configuration files that specify how a user-selected set of penetration objectives should be carried out. The system allows for penetration strategies to be attempted simultaneously and independently. Information from each strategy is shared with other strategies so each can be more effective, and together they form a very comprehensive approach to network penetration. The strategies can be throttled at different levels to allow for those that are more likely to achieve success to run at the highest speeds.