lacework-global-320
3.2.1 Ensure that the --anonymous-auth argument is set to false (Automated)
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Description
Disable anonymous requests to the Kubelet server.
Rationale
When enabled, requests that are not rejected by other configured authentication methods are treated as anonymous requests. These requests are then served by the Kubelet server. You should rely on authentication to authorize access and disallow anonymous requests.
Impact
Anonymous requests will be rejected.
Audit
Audit Method 1:
If using a Kubelet configuration file, check that there is an entry for authentication: anonymous: enabled
set to false
.
First, SSH to the relevant node:
Run the following command on each node to find the appropriate Kubelet config file:
ps -ef | grep kubelet
The output of the above command should return something similar to --config /etc/kubernetes/kubelet/kubelet-config.json
which is the location of the Kubelet config file.
Open the Kubelet config file:
sudo more /etc/kubernetes/kubelet/kubelet-config.json
Verify that the "authentication": { "anonymous": { "enabled": false }
argument is set to false
.
Audit Method 2:
If using the api configz endpoint consider searching for the status of authentication... "anonymous.*{"enabled":false}
by extracting the live configuration from the nodes running kubelet.
Set the local proxy port and the following variables and provide proxy port number and node name;
HOSTNAME_PORT="localhost-and-port-number"
NODE_NAME="The-Name-Of-Node-To-Extract-Configuration" from the output of "kubectl get nodes"
kubectl proxy --port=8001 &
export HOSTNAME_PORT=localhost:8001 (example host and port number)
export NODE_NAME=ip-192.168.31.226.ec2.internal (example node name from "kubectl get nodes")
curl -sSL "http://${HOSTNAME_PORT}/api/v1/nodes/${NODE_NAME}/proxy/configz"
Remediation
Remediation Method 1:
If modifying the Kubelet config file, edit the kubelet-config.json file /etc/kubernetes/kubelet/kubelet-config.json
and set the below parameter to false:
"authentication": { "anonymous": { "enabled": false } }
Remediation Method 2:
If using executable arguments, edit the kubelet service file /etc/systemd/system/kubelet.service.d/10-kubelet-args.conf
on each worker node and add the below parameter at the end of the KUBELET_ARGS
variable string:
--anonymous-auth=false
Remediation Method 3:
If using the api configz endpoint consider searching for the status of "authentication.*anonymous":{"enabled":false}"
by extracting the live configuration from the nodes running kubelet.
**See detailed step-by-step configmap procedures in Reconfigure a Node's Kubelet in a Live Cluster, and check for kubelet configuration changes
kubectl proxy --port=8001 &
export HOSTNAME_PORT=localhost:8001 (example host and port number)
export NODE_NAME=ip-192.168.31.226.ec2.internal (example node name from "kubectl get nodes")
curl -sSL "http://${HOSTNAME_PORT}/api/v1/nodes/${NODE_NAME}/proxy/configz"
For all three remediations: Based on the node's service manager (the example below is for systemctl), restart the kubelet service and check status:
systemctl daemon-reload
systemctl restart kubelet.service
systemctl status kubelet -l
References
https://kubernetes.io/docs/admin/kubelet/
https://kubernetes.io/docs/admin/kubelet-authentication-authorization/#kubelet-authentication
https://kubernetes.io/docs/tasks/administer-cluster/reconfigure-kubelet/