Containers should not mount the Docker socket docker.sock inside them
Set up the docker integration.
Description
The Docker socket docker.sock should not be mounted inside a container.
Rationale
If the Docker socket is mounted inside a container it could allow processes running within the container to execute Docker commands which would effectively allow for full control of the host.
Audit
Run this command: docker ps --quiet --all | xargs docker inspect --format '{{ .Id }}: Volumes={{ .Mounts }}' | grep docker.sock
This returns any instances where docker.sock
has been mapped to a container as a volume.
You should ensure that no containers mount docker.sock as a volume.
Impact
None
Default value
By default, docker.sock is not mounted inside containers.
References
- https://raesene.github.io/blog/2016/03/06/The-Dangers-Of-Docker.sock/
- https://forums.docker.com/t/docker-in-docker-vs-mounting-var-run-docker-sock/9450/2
- https://github.com/docker/docker/issues/21109
CIS controls
Version 6
9 Limitation and Control of Network Ports, Protocols, and Services