Identifies when an SNS topic message is published by a rare user in AWS. Adversaries may publish messages to SNS topics for phishing campaigns, data exfiltration, or lateral movement within the AWS environment. SNS topics are used to send notifications and messages to subscribed endpoints such as applications, devices or email addresses, making them a valuable target for adversaries to distribute malicious content or exfiltrate sensitive data. This is a [New Terms](https://www.elastic.co/guide/en/security/current/rules-ui-create.html#create-new-terms-rule) rule that only flags when this behavior is observed for the first time on a user in the last 14 days.