Failed copy jobs

My cross-account copy jobs are failing with this error message "AMI snapshot copy failed with error: Given key ID is not accessible. You must have DescribeKey permissions on the default CMK". I don't see anywhere in the CF templates where the member account keys are shared with the Central Backup account. Could this be the problem?

Start by inspecting the AWS CloudFormation templates for cross-account KMS key sharing between member accounts and the Central Backup account. Compare the configuration with the reported requirement for DescribeKey permissions on the default CMK. Done means determining whether missing key access causes the copy failure and documenting the required configuration or next diagnostic step.

Written by the indexing model from the issue text.