Control: 3.4 Ensure that docker.socket file permissions are set to 644 or more restrictive

Description

You should verify that the file permissions on the docker.socket file are correctly set to 644 or more restrictively.

The docker.socket file contains sensitive parameters that may alter the behavior of the Docker remote API. It should therefore be writeable only by root in order to ensure that it is not modified by less privileged users.

Remediation

Step 1: Find out the file location:

systemctl show -p FragmentPath docker.socket

Step 2: : If the file does not exist, this recommendation is not applicable. If the file does exist, you should execute the command below, including the correct file path to set the file permissions to 644. For example,

chmod 644 /usr/lib/systemd/system/docker.socket

Default Value

This file may not be present on the system and in that case, this recommendation is not applicable. By default, if the file is present, the permissions should be set to 644 or more restrictively.