[2023] CKS Answers CKS Free Demo Are Based On The Real Exam [Q22-Q45]

NO.22 Context
The kubeadm-created cluster’s Kubernetes API server was, for testing purposes, temporarily configured to allow unauthenticated and unauthorized access granting the anonymous user duster-admin access.
Task
Reconfigure the cluster’s Kubernetes API server to ensure that only authenticated and authorized REST requests are allowed.
Use authorization mode Node,RBAC and admission controller NodeRestriction.
Cleaning up, remove the ClusterRoleBinding for user system:anonymous.

NO.23 Cluster: scanner Master node: controlplane Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context scanner
Given: You may use Trivy’s documentation.
Task: Use the Trivy open-source container scanner to detect images with severe vulnerabilities used by Pods in the namespace nato.
Look for images with High or Critical severity vulnerabilities and delete the Pods that use those images. Trivy is pre-installed on the cluster’s master node. Use cluster’s master node to use Trivy.

NO.24 Fix all issues via configuration and restart the affected components to ensure the new setting takes effect.
Fix all of the following violations that were found against the API server:- a. Ensure that the RotateKubeletServerCertificate argument is set to true.
b. Ensure that the admission control plugin PodSecurityPolicy is set.
c. Ensure that the –kubelet-certificate-authority argument is set as appropriate.
Fix all of the following violations that were found against the Kubelet:- a. Ensure the –anonymous-auth argument is set to false.
b. Ensure that the –authorization-mode argument is set to Webhook.
Fix all of the following violations that were found against the ETCD:-
a. Ensure that the –auto-tls argument is not set to true
b. Ensure that the –peer-auto-tls argument is not set to true
Hint: Take the use of Tool Kube-Bench

NO.25 Create a new NetworkPolicy named deny-all in the namespace testing which denies all traffic of type ingress and egress traffic

NO.26 use the Trivy to scan the following images,

NO.27 You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context stage Context: A PodSecurityPolicy shall prevent the creation of privileged Pods in a specific namespace. Task: 1. Create a new PodSecurityPolcy named deny-policy, which prevents the creation of privileged Pods. 2. Create a new ClusterRole name deny-access-role, which uses the newly created PodSecurityPolicy deny-policy. 3. Create a new ServiceAccount named psd-denial-sa in the existing namespace development. Finally, create a new ClusterRoleBindind named restrict-access-bind, which binds the newly created ClusterRole deny-access-role to the newly created ServiceAccount psp-denial-sa

NO.28 You must complete this task on the following cluster/nodes: Cluster: immutable-cluster Master node: master1 Worker node: worker1 You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context immutable-cluster
Context: It is best practice to design containers to be stateless and immutable.
Task:
Inspect Pods running in namespace prod and delete any Pod that is either not stateless or not immutable.
Use the following strict interpretation of stateless and immutable:
1. Pods being able to store data inside containers must be treated as not stateless.
Note: You don’t have to worry whether data is actually stored inside containers or not already.
2. Pods being configured to be privileged in any way must be treated as potentially not stateless or not immutable.

NO.29 SIMULATION
Given an existing Pod named test-web-pod running in the namespace test-system Edit the existing Role bound to the Pod’s Service Account named sa-backend to only allow performing get operations on endpoints.
Create a new Role named test-system-role-2 in the namespace test-system, which can perform patch operations, on resources of type statefulsets.
Create a new RoleBinding named test-system-role-2-binding binding the newly created Role to the Pod’s ServiceAccount sa-backend.

NO.30 a. Retrieve the content of the existing secret named default-token-xxxxx in the testing namespace.
Store the value of the token in the token.txt
b. Create a new secret named test-db-secret in the DB namespace with the following content:
username: mysql
password: password@123
Create the Pod name test-db-pod of image nginx in the namespace db that can access test-db-secret via a volume at path /etc/mysql-credentials

NO.31 Context: Cluster: prod Master node: master1 Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context prod
Task: Analyse and edit the given Dockerfile (based on the ubuntu:18:04 image) /home/cert_masters/Dockerfile fixing two instructions present in the file being prominent security/best-practice issues.
Analyse and edit the given manifest file /home/cert_masters/mydeployment.yaml fixing two fields present in the file being prominent security/best-practice issues.
Note: Don’t add or remove configuration settings; only modify the existing configuration settings, so that two configuration settings each are no longer security/best-practice concerns. Should you need an unprivileged user for any of the tasks, use user nobody with user id 65535

NO.32 Cluster: admission-cluster
Master node: master
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context admission-cluster
Context:
A container image scanner is set up on the cluster, but it’s not yet fully integrated into the cluster’s configuration. When complete, the container image scanner shall scan for and reject the use of vulnerable images.
Task:
You have to complete the entire task on the cluster’s master node, where all services and files have been prepared and placed.
Given an incomplete configuration in directory /etc/Kubernetes/config and a functional container image scanner with HTTPS endpoint https://imagescanner.local:8181/image_policy:
1. Enable the necessary plugins to create an image policy
2. Validate the control configuration and change it to an implicit deny
3. Edit the configuration to point to the provided HTTPS endpoint correctly Finally, test if the configuration is working by trying to deploy the vulnerable resource /home/cert_masters/test-pod.yml Note: You can find the container image scanner’s log file at /var/log/policy/scanner.log

NO.33 You must complete this task on the following cluster/nodes: Cluster: immutable-cluster Master node: master1 Worker node: worker1 You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context immutable-cluster Context: It is best practice to design containers to be stateless and immutable. Task: Inspect Pods running in namespace prod and delete any Pod that is either not stateless or not immutable. Use the following strict interpretation of stateless and immutable: 1. Pods being able to store data inside containers must be treated as not stateless. Note: You don’t have to worry whether data is actually stored inside containers or not already. 2. Pods being configured to be privileged in any way must be treated as potentially not stateless or not immutable.

NO.34 Cluster: scanner
Master node: controlplane
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context scanner
Given:
You may use Trivy’s documentation.
Task:
Use the Trivy open-source container scanner to detect images with severe vulnerabilities used by Pods in the namespace nato.
Look for images with High or Critical severity vulnerabilities and delete the Pods that use those images.
Trivy is pre-installed on the cluster’s master node. Use cluster’s master node to use Trivy.

NO.35 Service is running on port 389 inside the system, find the process-id of the process, and stores the names of all the open-files inside the /candidate/KH77539/files.txt, and also delete the binary.

NO.36 SIMULATION
Using the runtime detection tool Falco, Analyse the container behavior for at least 20 seconds, using filters that detect newly spawning and executing processes in a single container of Nginx.
store the incident file art /opt/falco-incident.txt, containing the detected incidents. one per line, in the format
[timestamp],[uid],[processName]

NO.37 SIMULATION
Fix all issues via configuration and restart the affected components to ensure the new setting takes effect.
Fix all of the following violations that were found against the API server:- a. Ensure the –authorization-mode argument includes RBAC b. Ensure the –authorization-mode argument includes Node c. Ensure that the –profiling argument is set to false Fix all of the following violations that were found against the Kubelet:- a. Ensure the –anonymous-auth argument is set to false.
b. Ensure that the –authorization-mode argument is set to Webhook.
Fix all of the following violations that were found against the ETCD:-
a. Ensure that the –auto-tls argument is not set to true
Hint: Take the use of Tool Kube-Bench

NO.38 You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context dev Context: A CIS Benchmark tool was run against the kubeadm created cluster and found multiple issues that must be addressed. Task: Fix all issues via configuration and restart the affected components to ensure the new settings take effect. Fix all of the following violations that were found against the API server: 1.2.7 authorization-mode argument is not set to AlwaysAllow FAIL 1.2.8 authorization-mode argument includes Node FAIL 1.2.7 authorization-mode argument includes RBAC FAIL Fix all of the following violations that were found against the Kubelet: 4.2.1 Ensure that the anonymous-auth argument is set to false FAIL 4.2.2 authorization-mode argument is not set to AlwaysAllow FAIL (Use Webhook autumn/authz where possible) Fix all of the following violations that were found against etcd: 2.2 Ensure that the client-cert-auth argument is set to true

NO.39 Context
Your organization’s security policy includes:
ServiceAccounts must not automount API credentials
ServiceAccount names must end in “-sa”
The Pod specified in the manifest file /home/candidate/KSCH00301 /pod-m nifest.yaml fails to schedule because of an incorrectly specified ServiceAccount.
Complete the following tasks:
Task
1. Create a new ServiceAccount named frontend-sa in the existing namespace q a. Ensure the ServiceAccount does not automount API credentials.
2. Using the manifest file at /home/candidate/KSCH00301 /pod-manifest.yaml, create the Pod.
3. Finally, clean up any unused ServiceAccounts in namespace qa.

NO.40 Context:
Cluster: gvisor
Master node: master1
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context gvisor
Context: This cluster has been prepared to support runtime handler, runsc as well as traditional one.
Task:
Create a RuntimeClass named not-trusted using the prepared runtime handler names runsc.
Update all Pods in the namespace server to run on newruntime.

NO.41 SIMULATION
On the Cluster worker node, enforce the prepared AppArmor profile
#include <tunables/global>
profile docker-nginx flags=(attach_disconnected,mediate_deleted) {
#include <abstractions/base>
network inet tcp,
network inet udp,
network inet icmp,
deny network raw,
deny network packet,
file,
umount,
deny /bin/** wl,
deny /boot/** wl,
deny /dev/** wl,
deny /etc/** wl,
deny /home/** wl,
deny /lib/** wl,
deny /lib64/** wl,
deny /media/** wl,
deny /mnt/** wl,
deny /opt/** wl,
deny /proc/** wl,
deny /root/** wl,
deny /sbin/** wl,
deny /srv/** wl,
deny /tmp/** wl,
deny /sys/** wl,
deny /usr/** wl,
audit /** w,
/var/run/nginx.pid w,
/usr/sbin/nginx ix,
deny /bin/dash mrwklx,
deny /bin/sh mrwklx,
deny /usr/bin/top mrwklx,
capability chown,
capability dac_override,
capability setuid,
capability setgid,
capability net_bind_service,
deny @{PROC}/* w, # deny write for all files directly in /proc (not in a subdir)
# deny write to files not in /proc/<number>/** or /proc/sys/**
deny @{PROC}/{[^1-9],[^1-9][^0-9],[^1-9s][^0-9y][^0-9s],[^1-9][^0-9][^0-9][^0-9]*}/** w, deny @{PROC}/sys/[^k]** w, # deny /proc/sys except /proc/sys/k* (effectively /proc/sys/kernel) deny @{PROC}/sys/kernel/{?,??,[^s][^h][^m]**} w, # deny everything except shm* in /proc/sys/kernel/ deny @{PROC}/sysrq-trigger rwklx, deny @{PROC}/mem rwklx, deny @{PROC}/kmem rwklx, deny @{PROC}/kcore rwklx, deny mount, deny /sys/[^f]*/** wklx, deny /sys/f[^s]*/** wklx, deny /sys/fs/[^c]*/** wklx, deny /sys/fs/c[^g]*/** wklx, deny /sys/fs/cg[^r]*/** wklx, deny /sys/firmware/** rwklx, deny /sys/kernel/security/** rwklx,
}
Edit the prepared manifest file to include the AppArmor profile.
apiVersion: v1
kind: Pod
metadata:
name: apparmor-pod
spec:
containers:
– name: apparmor-pod
image: nginx
Finally, apply the manifests files and create the Pod specified on it.
Verify: Try to use command ping, top, sh

NO.42 SIMULATION
A container image scanner is set up on the cluster.
Given an incomplete configuration in the directory
/etc/Kubernetes/confcontrol and a functional container image scanner with HTTPS endpoint https://acme.local.8081/image_policy
1. Enable the admission plugin.
2. Validate the control configuration and change it to implicit deny.
Finally, test the configuration by deploying the pod having the image tag as the latest.

NO.43 Create a PSP that will only allow the persistentvolumeclaim as the volume type in the namespace restricted.
Create a new PodSecurityPolicy named prevent-volume-policy which prevents the pods which is having different volumes mount apart from persistentvolumeclaim.
Create a new ServiceAccount named psp-sa in the namespace restricted.
Create a new ClusterRole named psp-role, which uses the newly created Pod Security Policy prevent-volume-policy
Create a new ClusterRoleBinding named psp-role-binding, which binds the created ClusterRole psp-role to the created SA psp-sa.
Hint:
Also, Check the Configuration is working or not by trying to Mount a Secret in the pod maifest, it should get failed.
POD Manifest:
apiVersion: v1
kind: Pod
metadata:
name:
spec:
containers:
– name:
image:
volumeMounts:
– name:
mountPath:
volumes:
– name:
secret:
secretName:

NO.44 Using the runtime detection tool Falco, Analyse the container behavior for at least 20 seconds, using filters that detect newly spawning and executing processes in a single container of Nginx.

NO.45 A container image scanner is set up on the cluster.
Given an incomplete configuration in the directory
/etc/Kubernetes/confcontrol and a functional container image scanner with HTTPS endpoint https://acme.local.8081/image_policy