How to find Amazon S3 bucket misconfigurations and fix them ASAP

This report describes how accidental Amazon S3 bucket misconfigurations can expose data publicly, outlines how to detect and investigate such incidents (e.g., searching for PutBucketAcl events and ACLs granting AllUsers/AuthenticatedUsers), lists four red flags to prioritize (suspicious source IP, unusual user behavior, sensitive bucket names, and excessive permissions), presents an Expel case study, and recommends mitigations such as SIEM queries, AWS Config monitoring, and operational checks.