Kubernetes Kubelet must enable kernel protection.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-242434	CNTR-K8-001620	SV-242434r918188_rule		High

Description
System kernel is responsible for memory, disk, and task management. The kernel provides a gateway between the system hardware and software. Kubernetes requires kernel access to allocate resources to the Control Plane. Threat actors that penetrate the system kernel can inject malicious code or hijack the Kubernetes architecture. It is vital to implement protections through Kubernetes components to reduce the attack surface.

Description

System kernel is responsible for memory, disk, and task management. The kernel provides a gateway between the system hardware and software. Kubernetes requires kernel access to allocate resources to the Control Plane. Threat actors that penetrate the system kernel can inject malicious code or hijack the Kubernetes architecture. It is vital to implement protections through Kubernetes components to reduce the attack surface.

STIG	Date
Kubernetes Security Technical Implementation Guide	2023-08-29

Details

Check Text ( C-45709r918186_chk )
On the Control Plane, run the command: ps -ef \| grep kubelet If the "--protect-kernel-defaults" option exists, this is a finding. Note the path to the config file (identified by --config). Run the command: grep -i protectKernelDefaults If the setting "protectKernelDefaults" is not set or is set to false, this is a finding.

Fix Text (F-45667r918187_fix)
On the Control Plane, run the command: ps -ef \| grep kubelet Remove the "--protect-kernel-defaults" option if present. Note the path to the Kubernetes Kubelet config file (identified by --config). Edit the Kubernetes Kubelet config file: Set "protectKernelDefaults" to "true". Restart the kubelet service using the following command: systemctl daemon-reload && systemctl restart kubelet