event.dataset: "aws.cloudtrail"
and event.provider: "iam.amazonaws.com"
and event.action: "CreateUser"
and event.outcome: "success"
and aws.cloudtrail.user_identity.type: "AssumedRole"
and aws.cloudtrail.user_identity.arn: *i-*
Install detection rules in Elastic Security
Detect AWS IAM Create User via Assumed Role on EC2 Instance in the Elastic Security detection engine by installing this rule into your Elastic Stack.
To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).