# Cis Docker 3.23

> Cis Docker 3.23 is an Agent Skill for devops & security published in the CyberStrikeus/CyberStrike repository on GitHub: a SKILL.md instruction file an AI agent can load to do this task.

Ensure that the Containerd socket file ownership is set to root:root

- Skill name: `cis-docker-3.23`
- Category: [DevOps & Security](https://www.openparable.com/skill/devops-security/1)
- Source: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Server_Software/Docker/CIS_Docker_Benchmark_v1.8.0/cis-docker-3.23/SKILL.md
- Repository: CyberStrikeus/CyberStrike (1,211 GitHub stars when collected)

## SKILL.md

# Ensure that the Containerd socket file ownership is set to root:root (Automated)

## Profile Applicability

- Level 1 - Docker - Linux

## Description

You should verify that the Containerd socket file is owned by `root` and group owned by `root`.

## Rationale

Containerd is an underlying component used by Docker to create and manage containers. It provides a socket file similar to the Docker socket, which must be protected from unauthorized access. If any other user or process owns this socket, it might be possible for that non-privileged user or process to interact with the Containerd daemon. Additionally, in this case a non-privileged user or process might be able to interact with containers which is neither a secure nor desired behavior.

Unlike the Docker socket, there is usually no requirement for non-privileged users to connect to the socket, so the ownership should be root:root.

## Impact

None.

## Audit Procedure

You should execute the below command to verify that the Containerd socket file is owned by `root` and group owned by `root`:

```bash
stat -c %U:%G /run/containerd/containerd.sock | grep -v root:root
```

The command above should return no results.

## Remediation

You should execute the following command:

```bash
chown root:root /run/containerd/containerd.sock
```

This sets the ownership to `root` and group ownership to `root` for the default Containerd socket file.

## Default Value

By default, the ownership and group ownership for the Containerd socket file is correctly set to `root:root`.

## References

None specified in benchmark.

## 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                                                                                                                                                                                                                                  |      |      |      |

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Source: https://www.openparable.com/skill/devops-security/cis-docker-3-23 (OpenParable). Cite the canonical URL above.