The AWS RDS Snapshot Shared detection rule identifies events where an Amazon RDS snapshot is shared with another AWS account, which could be a potential indicator of data exfiltration. The rule is triggered by monitoring AWS CloudTrail logs for specific management events related to the modification of DB snapshot attributes. When the attribute 'restore' of a snapshot is modified to include another AWS account ID, the rule flags this activity as suspicious. The presence of such modifications implies that data could potentially be transferred or restored in another account, raising security concerns. To mitigate these risks, the rule emphasizes verifying the intent behind the snapshot sharing and ensuring that it aligns with organizational policies. If it is determined that the sharing was unintentional or unauthorized, the rule recommends removing the sharing and isolating the IAM user involved in the action. Additionally, relevant documentation from AWS regarding snapshot sharing provides users with the guidance they need to manage RDS snapshots securely.