Use StackSets to centrally manage deployments to all the accounts in your organization or specific organizational units (OUs) in AWS Organizations. You can enable automatic deployments to any new accounts added to your organization or OUs. The permissions needed to deploy across accounts will automatically be handled by StackSets. For more information, see Working with AWS CloudFormation StackSets.
When using dynamic references, you can now have CloudFormation use the latest version of an SSM parameter whenever you create or update a stack. You are no longer required to specify a specific version.