cyberstrikeus 4.2.7 Ensure that the --hostname-override argument is not set (Manual)
Profile Applicability
- Level 1 - Worker Node
Description
Do not override node hostnames.
Rationale
Overriding hostnames could potentially break TLS setup between the kubelet and the apiserver. Additionally, with overridden hostnames, it becomes increasingly difficult to associate logs with a particular node and process them for security analytics. Hence, you should setup your kubelet nodes with resolvable FQDNs and avoid overriding the hostnames with IPs.
Impact
Some cloud providers may require this flag to ensure that hostname matches names issued by the cloud provider. In these environments, this recommendation should not apply.
Audit
Run the following command on each node:
ps -ef | grep kubelet
Verify that --hostname-override argument does not exist.
Note This setting is not configurable via the Kubelet config file.
Remediation
Edit the kubelet service file /etc/systemd/system/kubelet.service.d/10-kubeadm.conf on each worker node and remove the --hostname-override argument from the KUBELET_SYSTEM_PODS_ARGS variable.
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Default Value
By default, --hostname-override argument is not set.
References
CIS Controls
| Controls Version | Control | IG 1 | IG 2 | IG 3 |
|---|---|---|---|---|
| v8 | 4 Secure Configuration of Enterprise Assets and Software - Establish and maintain the secure configuration of enterprise assets (end-user devices, including portable and mobile; network devices; non-computing/IoT devices; and servers) and software (operating systems and applications). | |||
| v7 | 5 Secure Configuration for Hardware and Software on Mobile Devices, Laptops, Workstations and Servers - Secure Configuration for Hardware and Software on Mobile Devices, Laptops, Workstations and Servers |