Cis K8s V200 4.1.10

---
name: cis-k8s-v200-4.1.10
description: "If the kubelet config.yaml configuration file is being used validate file ownership is set to root:root (Automated)"
category: cis-k8s
version: "2.0.0"
author: cyberstrike-official
tags: [cis, kubernetes, worker-node, config-files, file-ownership, kubelet-config]
cis_id: "4.1.10"
cis_benchmark: "CIS Kubernetes Benchmark v2.0.0"
tech_stack: [kubernetes]
cwe_ids: []
chains_with: []
prerequisites: []
severity_boost: {}
---

# 4.1.10 If the kubelet config.yaml configuration file is being used validate file ownership is set to root:root (Automated)

## Profile Applicability

- Level 1 - Worker Node

## Description

Ensure that if the kubelet refers to a configuration file with the `--config` argument, that file is owned by root:root.

## Rationale

The kubelet reads various parameters, including security settings, from a config file specified by the `--config` argument. If this file is specified you should restrict its file permissions to maintain the integrity of the file. The file should be owned by root:root.

## Impact

None

## Audit

Automated AAC auditing has been modified to allow CIS-CAT to input a variable for the `<PATH>/<FILENAME>` of the kubelet config yaml file.

Please set `$kubelet_config_yaml=<PATH><filename>` based on the file location on your system.

For example:

```bash
export kubelet_config_yaml=/var/lib/kubelet/config.yaml
```

To perform the audit manually: Run the below command (based on the file location on your system) on the each worker node. For example,

```bash
stat -c %U:%G /var/lib/kubelet/config.yaml
```

Verify that the ownership is set to `root:root`.

## Remediation

Run the following command (using the config file location identified in the Audit step)

```bash
chown root:root /etc/kubernetes/kubelet.conf
```

## Default Value

By default, `/var/lib/kubelet/config.yaml` file as set up by `kubeadm` is owned by `root:root`.

## References

1. https://kubernetes.io/docs/tasks/administer-cluster/kubelet-config-file/

## 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                                                                                                                                                                                                                                  |      |      |      |