Docker Enterprise older Universal Control Plane (UCP) and Docker Trusted Registry (DTR) images must be removed from all cluster nodes upon upgrading.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-235845	DKER-EE-004130	SV-235845r627662_rule		Medium

Description
When upgrading either the UCP or DTR components of Docker Enterprise, the newer images are pulled (or unpacked if offline) onto Engine nodes in a cluster. Once the upgrade is complete, one must manually remove all old image version from the cluster nodes to meet the requirements of this control. When upgrading the Docker Engine - Enterprise component of Docker Enterprise, the old package version is automatically replaced.

Description

When upgrading either the UCP or DTR components of Docker Enterprise, the newer images are pulled (or unpacked if offline) onto Engine nodes in a cluster. Once the upgrade is complete, one must manually remove all old image version from the cluster nodes to meet the requirements of this control. When upgrading the Docker Engine - Enterprise component of Docker Enterprise, the old package version is automatically replaced.

STIG	Date
Docker Enterprise 2.x Linux/UNIX Security Technical Implementation Guide	2021-03-26

Details

Check Text ( C-39064r627660_chk )
Verify that all outdated UCP and DTR container images have been removed from all nodes in the cluster. via CLI: As a Docker EE admin, execute the following command using a client bundle: docker images --filter reference='docker/[ucp\|dtr]*' Verify that there are no tags listed that are older than the currently installed versions of UCP and DTR. If any of the tags listed are older than the currently installed versions of UCP and DTR, then this is a finding.

Check Text ( C-39064r627660_chk )

Verify that all outdated UCP and DTR container images have been removed from all nodes in the cluster.

via CLI: As a Docker EE admin, execute the following command using a client bundle:

docker images --filter reference='docker/[ucp|dtr]*'

Verify that there are no tags listed that are older than the currently installed versions of UCP and DTR.

If any of the tags listed are older than the currently installed versions of UCP and DTR, then this is a finding.

Fix Text (F-39027r627661_fix)
Remove all outdated UCP and DTR container images from all nodes in the cluster: via CLI: As a Docker EE admin, execute the following commands using a client bundle: docker rmi -f $(docker images --filter reference='docker/ucp:[outdated_tags]' -q) docker rmi -f $(docker images --filter reference='docker/dtr:[outdated_tags]' -q)