C-0177 - Ensure that the --protect-kernel-defaults argument is set to true
Prerequisites
Run Kubescape with host sensor (see here)
Framework
cis-v1.23-t1.0.1, cis-aks-t1.2.0, cis-eks-t1.2.0
Severity
Low
Description of the the issue
Kernel parameters are usually tuned and hardened by the system administrators before putting the systems into production. These parameters protect the kernel and the system. Your kubelet kernel defaults that rely on such parameters should be appropriately set to match the desired secured system state. Ignoring this could potentially lead to running pods with undesired kernel behavior.
Related resources
What does this control test
Protect tuned kernel parameters from overriding kubelet default kernel parameter values.
How to check it manually
Run the following command on each node:
ps -ef | grep kubelet
Verify that the --protect-kernel-defaults
argument is set to true
.
If the --protect-kernel-defaults
argument is not present, check that there is a Kubelet config file specified by --config
, and that the file sets protectKernelDefaults
to true
.
Remediation
If using a Kubelet config file, edit the file to set protectKernelDefaults: true
.
If using command line arguments, edit the kubelet service file /etc/kubernetes/kubelet.conf
on each worker node and set the below parameter in KUBELET_SYSTEM_PODS_ARGS
variable.
--protect-kernel-defaults=true
Based on your system, restart the kubelet
service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Impact Statement
You would have to re-tune kernel parameters to match kubelet parameters.
Default Value
By default, --protect-kernel-defaults
is not set.
Example
No example
Updated 9 days ago