You are deploying a Cloud Build job that deploys Terraform code when a Git branch is updated. While testing, you noticed that the job fails. You see the following error in the build logs…

Changing to local state would eliminate the Cloud Storage backend issue but is not a recommended practice for collaborative Terraform development in a CI/CD pipeline, as it makes state management difficult for multiple users.

The error `Error 403` implies the bucket exists but access is denied; if the bucket was missing, the error would typically be 'bucket not found' or similar.

Granting `roles/owner` is an overly permissive role and goes against the principle of least privilege, as `roles/storage.objectAdmin` is sufficient and more secure for managing objects in a specific bucket.

The `Error 403` when querying Cloud Storage indicates a permission denied error. The Cloud Build service account, which executes the Terraform code using a Cloud Storage backend, requires the `roles/storage.objectAdmin` role on the specific Cloud Storage bucket to read and write Terraform state files, thus resolving the authentication issue with appropriate least privilege.