You can protect your content from unauthorized use through encryption. Store your encryption keys in AWS Secrets Manager, and then give the CodeBuild service role associated with the build project permission to obtain the encryption keys from your Secrets Manager account. For more information, see Encrypt build outputs using a customer managed key, Create a build project in AWS CodeBuild, Run AWS CodeBuild builds manually, and Tutorial: Storing and retrieving a secret.
Use the CODEBUILD_KMS_KEY_ID
environment variable in a build command to
obtain the AWS KMS key identifier. For more information, see Environment variables in build
environments.
You can use Secrets Manager to protect credentials to a private registry that stores a Docker image used for your runtime environment. For more information, see Private registry with AWS Secrets Manager sample for CodeBuild.