Attacking Serverless Servers Reverse Engineering the AWS, Azure, and GCP Function Runtimes | SANS

The cloud makes it easy for developers to launch their applications, integrate with managed services, and think little about the underlying infrastructure. Unfortunately, this can and has come back to bite us. Last year's Capital One breach has made security professionals all too aware of the internal details of AWS, such as the EC2 Instance Metadata Service, which allowed a malicious actor to steal credentials for an IAM role that enabled them to pilfer documents from countless S3 buckets.

The serverless ecosystem is no different. In order to give our functions access to the cloud services they need, the cloud provider needs to provide them with the necessary credentials. If a function's runtime is owned, so are these credentials. This presentation will explain how a compromised serverless function can be used to exfiltrate sensitive data, persist malware, gain powerful credentials, and pivot to other cloud services. It will contain live demonstrations of creating and exploiting reverse shell connections for AWS Lambda, Azure Functions, and Google Cloud Functions. These malicious functions and associated research have been published on GitHub by Brandon Evans and Eric Johnson under a repository called "Serverless Prey" (https://github.com/pumasecurity/serve....

Brandon Evans, SANS Associate Instructor

Brandon is a Senior Application Security Engineer at Asurion, where he provides security services for thousands of his coworkers in product development across several global sites responsible for hundreds of web applications. As an application developer for most of his professional career, he moved into security full-time largely because of his many formal trainings through SANS. Brandon is lead author for the new SEC510: Multicloud Security Assessment and Defense and a contributor and instructor for SEC540: Cloud Security and DevOps Automation.