Lightweight Cloud Application Sandboxing

Modern cloud applications can quickly grow to an elaborate and intricate tangle of services. In this scenario, paying attention to security aspects is important to mitigate the impact of incidents. Indeed, several research works and industrial standards recommend the integration of least privilege policies to prevent disruptions such as file system tampering. Unfortunately, technologies like containers virtualize file system resources with a volume-based approach, which may be overly coarse. In this work we address this problem proposing an approach that restrict application access to file system resources with a resource-based granularity. To this end, we develop a flexible and intuitive tool that relies on instrumentation to collect, merge, and audit the activity traces generated by any application component. We then demonstrate how this information is used to create fine-grained access policies, and introduce sandboxing using recent kernel security modules, strengthening the security boundary of the whole application. In the experimental evaluation we showcase the mitigation capabilities associated with our approach, and the low performance footprint. The proposal is associated with an open source implementation.