AWS::CloudFormation::Authentication not working on eu-central-1

[w32-blaster]

AWS::CloudFormation::Authentication mechanism can not be used when authenticating to S3 in a bucket located in eu-central-1 (Frankfurt) region. This is because that region only supports authentication with AWS4-HMAC-SHA256.

Please clarify this in the documentation or give examples how to use it when working in that region.

[rachfop]

The resource specification reports what is allowed in each region: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cfn-resource-specification.html