Cis K8s V1110 2.7

---
name: cis-k8s-v1110-2.7
description: "Ensure that the --peer-auto-tls argument is not set to true (Automated)"
category: cis-k8s
version: "1.11.0"
author: cyberstrike-official
tags: [cis, kubernetes, etcd, peer-auto-tls, tls]
cis_id: "2.7"
cis_benchmark: "CIS Kubernetes Benchmark v1.11.0"
tech_stack: [kubernetes]
cwe_ids: []
chains_with: []
prerequisites: []
severity_boost: {}
---

# 2.7 Ensure that the --peer-auto-tls argument is not set to true (Automated)

## Profile Applicability

- Level 1 - Master Node

## Description

Do not use automatically generated self-signed certificates for TLS connections between peers.

## Rationale

etcd is a highly-available key value store used by Kubernetes deployments for persistent storage of all of its REST API objects. These objects are sensitive in nature and should be accessible only by authenticated etcd peers in the etcd cluster. Hence, do not use self-signed certificates for authentication.

## Impact

All peers attempting to communicate with the etcd server will require a valid client certificate for authentication.

## Audit

Run the following command on the etcd server node:

```bash
ps -ef | grep etcd
```

Verify that if the `--peer-auto-tls` argument exists, it is not set to `true`.
Note: This recommendation is applicable only for etcd clusters. If you are using only one etcd server in your environment then this recommendation is not applicable.

## Remediation

Edit the etcd pod specification file `/etc/kubernetes/manifests/etcd.yaml` on the master node and either remove the `--peer-auto-tls` parameter or set it to `false`.

```
--peer-auto-tls=false
```

## Default Value

Note: This recommendation is applicable only for etcd clusters. If you are using only one etcd server in your environment then this recommendation is not applicable.

By default, `--peer-auto-tls` argument is set to `false`.

## References

1. https://coreos.com/etcd/docs/latest/op-guide/security.html
2. https://kubernetes.io/docs/admin/etcd/
3. https://coreos.com/etcd/docs/latest/op-guide/configuration.html#peer-auto-tls

## CIS Controls

| Controls Version | Control                  | IG 1 | IG 2 | IG 3 |
| ---------------- | ------------------------ | ---- | ---- | ---- |
| v8               | 5.2 Use Unique Passwords | X    | X    | X    |
| v7               | 4.4 Use Unique Passwords |      | X    | X    |