Biblio

Timely and adequate response on the computer security incidents depends on the accurate monitoring of the security situation. The paper investigates the task of refinement of the attack models in the form of attack graphs. It considers some challenges of attack graph generation and possible solutions, including: inaccuracies in specifying the pre- and postconditions of attack actions, processing of cycles in graphs to apply the Bayesian methods for attack graph analysis, mapping of incidents on attack graph nodes, and automatic countermeasure selection for the nodes under the risk. The software prototype that implements suggested solutions is briefly specified. The influence of the modifications on the security monitoring is shown on a case study, and the results of experiments are described.

The paper suggests several techniques for computer network risk assessment based on Common Vulnerability Scoring System (CVSS) and attack modeling. Techniques use a set of integrated security metrics and consider input data from security information and event management (SIEM) systems. Risk assessment techniques differ according to the used input data. They allow to get risk assessment considering requirements to the accuracy and efficiency. Input data includes network characteristics, attacks, attacker characteristics, security events and countermeasures. The tool that implements these techniques is presented. Experiments demonstrate operation of the techniques for different security situations.

One of the important direction of research in situational awareness is implementation of visual analytics techniques which can be efficiently applied when working with big security data in critical operational domains. The paper considers a visual analytics technique for displaying a set of security metrics used to assess overall network security status and evaluate the efficiency of protection mechanisms. The technique can assist in solving such security tasks which are important for security information and event management (SIEM) systems. The approach suggested is suitable for displaying security metrics of large networks and support historical analysis of the data. To demonstrate and evaluate the usefulness of the proposed technique we implemented a use case corresponding to the Olympic Games scenario.