Linux Foundation CKS actual dump : Certified Kubernetes Security Specialist (CKS)

Correct Answer:

Kubernetes auditing provides a security-relevant chronological set of records about a cluster. Kube-apiserver performs auditing. Each request on each stage of its execution generates an event, which is then pre-processed according to a certain policy and written to a backend. The policy determines what's recorded and the backends persist the records.
You might want to configure the audit log as part of compliance with the CIS (Center for Internet Security) Kubernetes Benchmark controls.
The audit log can be enabled by default using the following configuration in cluster.yml:
services:
kube-api:
audit_log:
enabled: true
When the audit log is enabled, you should be able to see the default values at /etc/kubernetes/audit-policy.yaml The log backend writes audit events to a file in JSONlines format. You can configure the log audit backend using the following kube-apiserver flags:
--audit-log-path specifies the log file path that log backend uses to write audit events. Not specifying this flag disables log backend. - means standard out
--audit-log-maxage defined the maximum number of days to retain old audit log files
--audit-log-maxbackup defines the maximum number of audit log files to retain
--audit-log-maxsize defines the maximum size in megabytes of the audit log file before it gets rotated If your cluster's control plane runs the kube-apiserver as a Pod, remember to mount the hostPath to the location of the policy file and log file, so that audit records are persisted. For example:
--audit-policy-file=/etc/kubernetes/audit-policy.yaml \
--audit-log-path=/var/log/audit.log

Correct Answer:

See the Explanation below for complete solution
Explanation:
1) Connect to the correct host
ssh cks000037
sudo -i
2) Remove user developer from the docker group ONLY
2.1 Verify current groups (optional but fast)
id developer
2.2 Remove ONLY from docker group
gpasswd -d developer docker
2.3 Verify removal
id developer
✅ docker should not appear; other groups must remain.
3) Reconfigure Docker to secure the socket and disable TCP
Docker config file:
vi /etc/docker/daemon.json
3.1 Set socket group to root and disable TCP listeners
Ensure the file contains exactly these relevant settings (merge with existing JSON if present):
{
"group": "root",
"hosts": ["unix:///var/run/docker.sock"]
}
Important:
"group": "root" → docker.sock owned by group root
"hosts" includes ONLY the unix socket (no tcp://)
If the file already exists with other keys, add/adjust only these keys and keep valid JSON (commas!).
Save and exit:
:wq
4) Restart Docker daemon
systemctl daemon-reload
systemctl restart docker
systemctl status docker --no-pager
5) Verify Docker socket ownership and permissions
ls -l /var/run/docker.sock
Expected:
srw-rw---- 1 root root ...
✅ Owner: root
✅ Group: root
6) Verify Docker is NOT listening on TCP
ss -lntp | grep docker
Expected:
No output (or nothing bound to TCP by dockerd)
Optional double-check:
ps aux | grep dockerd | grep -v grep
Ensure no -H tcp://... flags.
7) Ensure Kubernetes cluster is healthy
7.1 Check node and pods
export KUBECONFIG=/etc/kubernetes/admin.conf
kubectl get nodes
kubectl get pods -A
All nodes should be Ready, core pods Running.

Correct Answer:

SeetheExplanationbelowExplanation:
ssh-add ~/.ssh/tempprivate
eval "$(ssh-agent -s)"
cd contrib/terraform/aws
vi terraform.tfvars
terraform init
terraform apply -var-file=credentials.tfvars
ansible-playbook -i ./inventory/hosts ./cluster.yml -e ansible_ssh_user=core -e bootstrap_os=coreos -b --become-user=root --flush-cache -e ansible_user=core

Correct Answer:

See the Explanation below
Explanation:

Correct Answer:

See the Explanation below
Explanation:
worker1 $ vim /var/lib/kubelet/config.yaml
anonymous:
enabled: true #Delete this
enabled: false #Replace by this
authorization:
mode: AlwaysAllow #Delete this
mode: Webhook #Replace by this
worker1 $ systemctl restart kubelet. # To reload kubelet config
ssh to master1
master1 $ vim /etc/kubernetes/manifests/kube-apiserver.yaml
- -- authorization-mode=Node,RBAC
master1 $ vim /etc/kubernetes/manifests/etcd.yaml
- --client-cert-auth=true
Explanation:
ssh to worker1
worker1 $ vim /var/lib/kubelet/config.yaml
apiVersion: kubelet.config.k8s.io/v1beta1
authentication:
anonymous:
enabled: true #Delete this
enabled: false #Replace by this
webhook:
cacheTTL: 0s
enabled: true
x509:
clientCAFile: /etc/kubernetes/pki/ca.crt
authorization:
mode: AlwaysAllow #Delete this
mode: Webhook #Replace by this
webhook:
cacheAuthorizedTTL: 0s
cacheUnauthorizedTTL: 0s
cgroupDriver: systemd
clusterDNS:
- 10.96.0.10
clusterDomain: cluster.local
cpuManagerReconcilePeriod: 0s
evictionPressureTransitionPeriod: 0s
fileCheckFrequency: 0s
healthzBindAddress: 127.0.0.1
healthzPort: 10248
httpCheckFrequency: 0s
imageMinimumGCAge: 0s
kind: KubeletConfiguration
logging: {}
nodeStatusReportFrequency: 0s
nodeStatusUpdateFrequency: 0s
resolvConf: /run/systemd/resolve/resolv.conf
rotateCertificates: true
runtimeRequestTimeout: 0s
staticPodPath: /etc/kubernetes/manifests
streamingConnectionIdleTimeout: 0s
syncFrequency: 0s
volumeStatsAggPeriod: 0s
worker1 $ systemctl restart kubelet. # To reload kubelet config
ssh to master1
master1 $ vim /etc/kubernetes/manifests/kube-apiserver.yaml

master1 $ vim /etc/kubernetes/manifests/etcd.yaml