cis-docker-3.3

DevOps & Security

Ensure that docker.socket file ownership is set to root:root

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Ensure that docker.socket file ownership is set to root:root (Automated)

Profile Applicability

Level 1 - Docker - Linux

Description

You should verify that the docker.socket file ownership and group ownership are correctly set to root.

Rationale

The docker.socket file contains sensitive parameters that may alter the behavior of the Docker remote API. For this reason, it should be owned and group owned by root in order to ensure that it is not modified by less privileged users.

Impact

None.

Audit Procedure

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 exists, execute the command below, including the correct file path to verify that the file is owned and group-owned by root.

For example:

stat -c %U:%G /usr/lib/systemd/system/docker.socket | grep -v root:root

The command above should not return a value.

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 exists, execute the command below, including the correct file path to set the ownership and group ownership for the file to root.

For example:

chown root:root /usr/lib/systemd/system/docker.socket

Default Value

This file may not be present on the system. In that case, this recommendation is not applicable. By default, if the file is present, the ownership and group ownership for it should be set to root.

References

https://docs.docker.com/engine/reference/commandline/dockerd/#daemon-socket-option

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	5.4 Restrict Administrator Privileges to Dedicated Administrator Accounts - Restrict administrator privileges to dedicated administrator accounts on enterprise assets. Conduct general computing activities, such as internet browsing, email, and productivity suite use, from the user's primary, non-privileged account.	●	●	●
v7	4 Controlled Use of Administrative Privileges - Controlled Use of Administrative Privileges