STRonG: System Topology Risk Analysis on Graphs

Lars Schneidenbach, Sandhya Koteshwara, Martin Ohmacht, Apoorve Mohan, Eun Kyung Lee

Abstract: Production systems run complex stacks comprising constantly-evolving hardware and software components. Vulnerabilities in such stacks continuously pose security risks to both the service provider and customers, thus calling for a solution to analyze and quantify security risks. STRonG is a framework that leverages a layered graph-based approach to model, analyze, and quantify security risks in complex software and hardware stacks of systems. We propose using adjustable templates/stencils for relatively tractable and consistent modeling and allow user-defined scoring methods to be applied. STRonG quantitatively assesses how structure, components, or attribute modifications impact the security risk of critical parts of a system stack during the design or early stages of the development process. The framework’s efficacy is demonstrated by applying STRonG to the control stack of OpenStack cloud infrastructure and performing risk assessment before and after introducing a novel security layer, Secure Hypervisor Channel (SHC). We also demonstrate how introducing SHC can quantitatively reduce system risk.