The provided rule is designed to detect the deletion of Amazon Relational Database Service (RDS) Security Groups as part of monitoring AWS CloudTrail logs. Security Groups function as virtual firewalls that manage inbound and outbound traffic for RDS instances, making their unauthorized deletion a potential indicator of malicious activity. The rule operates by querying specific AWS CloudTrail events within a time frame of the last hour, focusing on successful deletion actions by users or roles interacting with RDS. It uses a KQL query to filter logs for relevant deletion actions and incorporates best practices for triage and response. False positives may arise from legitimate administrative actions, necessitating thorough investigation steps like reviewing user identities, event times, and correlating with other security activities. Further, it outlines corrective actions, including isolation of the affected resources, audit of permissions, and escalation procedures to ensure comprehensive incident response. The low severity and risk score of 21 reflect that, while deletions should be monitored, they may not always indicate a critical security breach.