Cross Account Role Access

Before you do this, please read about the cross account role access at first:
https://aws.amazon.com/blogs/apn/securely-accessing-customer-aws-accounts-with-cross-account-iam-roles/

Create Cross-Account Role to grant ADT Access to your S3 Bucket

1. Download the CloudFormation Template for the cross-account role.

2. Create a new CloudFormation Stack in AWS CloudFormation Service:

3. Fill the form for creating the stack:

• External id and the ADT account ID (MasterAccountName) are contains in the onboarding email.

4. Build the stack.