Privileged containers are not used
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Privileged containers are not used

docker

Classification:

compliance

Framework:

cis-docker

Control:

5.4

Overview

Description

Using the --privileged flag provides all Linux kernel capabilities to the container to which it is applied and therefore overwrites the --cap-add and --cap-drop flags. For this reason, ensure that it is not used.

Rationale

The --privileged flag provides all capabilities to the container to which it is applied, and also lifts all the limitations enforced by the device cgroup controller. As a consequence this the container has most of the rights of the underlying host. This flag only exists to allow for specific use cases (for example running Docker within Docker) and should not generally be used.

Audit

Run this command: docker ps --quiet --all | xargs docker inspect --format '{{ .Id }}: Privileged={{ .HostConfig.Privileged }}' This command returns Privileged=false for each container instance.

Remediation

Do not run containers with the --privileged flag. For example, do not start a container using the command docker run --interactive --tty --privileged centos /bin/bash

Impact

If you start a container without the --privileged flag, it will not have excessive default capabilities.

Default Value

False

References

  1. https://docs.docker.com/engine/reference/run/#runtime-privilege-and-linux-capabilities

CIS Controls

Version 6

5.1 Minimize And Sparingly Use Administrative Privileges Minimize administrative privileges and only use administrative accounts when they are required. Implement focused auditing on the use of administrative privileged functions and monitor for anomalous behavior.