# Disallow latest image tag The `:latest` tag is mutable and can lead to unexpected errors if the upstream image changes. A best practice is to use an immutable tag that maps to a specific and tested version of an application image. ## Policy YAML [disallow_latest_tag.yaml](best_practices/disallow_latest_tag.yaml) ````yaml apiVersion : kyverno.io/v1 kind: ClusterPolicy metadata: name: disallow-latest-tag spec: validationFailureAction: audit rules: - name: require-image-tag match: resources: kinds: - Pod validate: message: "An image tag is required" pattern: spec: containers: - image: "*:*" - name: validate-image-tag match: resources: kinds: - Pod validate: message: "Using a mutable image tag e.g. 'latest' is not allowed" pattern: spec: containers: - image: "!*:latest" ````