Correct Answer:

See the Explanation below for complete solution
Explanation:
1) Connect to the correct host
ssh cks000031
sudo -i
2) Use admin kubeconfig (safe default)
export KUBECONFIG=/etc/kubernetes/admin.conf
PART A - Deny ALL ingress traffic in prod namespace
Requirement:
NetworkPolicy name: deny-policy
Namespace: prod (namespace is labeled env=prod)
Effect: block all ingress
3) Create deny-policy in prod
Create the policy directly with kubectl (fastest & safest):
cat <<EOF | kubectl apply -f -
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: deny-policy
namespace: prod
spec:
podSelector: {}
policyTypes:
- Ingress
EOF
✅ What this does:
podSelector: {} → selects all Pods in prod
No ingress: rules → deny all ingress traffic
4) Verify
kubectl -n prod get networkpolicy deny-policy
PART B - Allow ingress to data ONLY from Pods in prod
Requirement:
NetworkPolicy name: allow-from-prod
Namespace: data (namespace is labeled env=data)
Allow ingress only from Pods in prod namespace
Use namespace label (env=prod)
5) Create allow-from-prod policy in data
cat <<EOF | kubectl apply -f -
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: allow-from-prod
namespace: data
spec:
podSelector: {}
policyTypes:
- Ingress
ingress:
- from:
- namespaceSelector:
matchLabels:
env: prod
EOF
✅ What this does:
Applies to all Pods in data
Allows ingress only from namespaces labeled env=prod
All other ingress traffic is denied by default
6) Verify
kubectl -n data get networkpolicy allow-from-prod
FINAL CHECK (What the examiner expects)
kubectl get networkpolicy -n prod
kubectl get networkpolicy -n data
You should see:
deny-policy in prod
allow-from-prod in data

Correct Answer:

See the Explanation below for complete solution
Explanation:
1) SSH to control-plane node
ssh cks000002
sudo -i
2) Edit API Server static pod manifest
API server in kubeadm runs as a static pod.
vi /etc/kubernetes/manifests/kube-apiserver.yaml
3) Apply required API Server security settings
3.1 Forbid anonymous authentication
Find command: section and ensure this line exists:
- --anonymous-auth=false
3.2 Use authorization mode Node,RBAC
Ensure exactly this line exists (and no AlwaysAllow):
- --authorization-mode=Node,RBAC
❌ Remove if present:
- --authorization-mode=AlwaysAllow
3.3 Enable admission controller NodeRestriction
Find --enable-admission-plugins and ensure NodeRestriction is included.
Correct example:
- --enable-admission-plugins=NodeRestriction
If other plugins already exist, append NodeRestriction, e.g.:
- --enable-admission-plugins=NamespaceLifecycle,ServiceAccount,NodeRestriction
4) Save file and let kubelet restart API server
Just save and exit (:wq)
Kubelet will automatically restart the API server pod.
5) Switch kubectl to secured config
Current kubectl will stop working after API server hardening.
export KUBECONFIG=/etc/kubernetes/admin.conf
Verify access:
kubectl get nodes
6) Remove insecure ClusterRoleBinding
Delete system:anonymous binding:
kubectl delete clusterrolebinding system:anonymous
Verify removal:
kubectl get clusterrolebinding | grep anonymous
(no output = correct)
7) Quick validation (optional but fast)
API server flags check:
grep -n "anonymous-auth" /etc/kubernetes/manifests/kube-apiserver.yaml
grep -n "authorization-mode" /etc/kubernetes/manifests/kube-apiserver.yaml grep -n "NodeRestriction" /etc/kubernetes/manifests/kube-apiserver.yaml

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 cks000036
sudo -i
export KUBECONFIG=/etc/kubernetes/admin.conf
2) Confirm the failing Pods + see the PSA error (fast)
kubectl -n confidential get deploy
kubectl -n confidential get pods
kubectl -n confidential describe deploy <deployment-name> | sed -n '/Events/,$p' (You'll usually see "violates PodSecurity 'restricted' ..." with the exact missing fields.)
3) Edit the provided manifest
vi /home/candidate/nginx-unprivileged.yaml
You must ensure the Pod template becomes compliant. Add/ensure the following exact blocks:
4) Add Pod-level securityContext (under spec.template.spec)
Find:
spec:
template:
spec:
Add this block under it (or merge if securityContext: already exists):
securityContext:
runAsNonRoot: true
runAsUser: 65535
seccompProfile:
type: RuntimeDefault
5) Add Container-level securityContext (under the nginx container)
Find:
containers:
- name: ...
image: ...
Under that container, add (or adjust) this exact block:
securityContext:
allowPrivilegeEscalation: false
readOnlyRootFilesystem: true
capabilities:
drop:
- ALL
If there are multiple containers, apply the same container securityContext to each one.
Save and exit:
:wq
6) Apply the manifest to the confidential namespace
kubectl -n confidential apply -f /home/candidate/nginx-unprivileged.yaml Wait rollout:
kubectl -n confidential rollout status deployment/<deployment-name>
If you don't know the deployment name from the file, list:
kubectl -n confidential get deploy
7) Verify Pods are running
kubectl -n confidential get pods -o wide
If still failing, show the exact PSA violation (this tells you what else to fix):
kubectl -n confidential describe pod <pod-name> | sed -n '/Events/,$p'
Quick "if it still fails" fixes (common restricted blockers)
Open the manifest again and ensure these are NOT set (or are removed/false):
hostNetwork: true
hostPID: true
hostIPC: true
any hostPort:
privileged: true
capabilities.add:
seccompProfile: Unconfined
runAsUser: 0 or runAsNonRoot: false
Then re-apply.
Minimal compliant result (what the grader expects)
Your Pod template should include:
seccompProfile: RuntimeDefault
runAsNonRoot: true (and a non-root UID like 65535)
container: allowPrivilegeEscalation: false
container: capabilities.drop: [ALL]
container: readOnlyRootFilesystem: true

Correct Answer:

See the Explanation belowExplanation:
Create psp to disallow privileged container
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: deny-access-role
rules:
- apiGroups: ['policy']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames:
- "deny-policy"
k create sa psp-denial-sa -n development
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: restrict-access-bing
roleRef:
kind: ClusterRole
name: deny-access-role
apiGroup: rbac.authorization.k8s.io
subjects:
- kind: ServiceAccount
name: psp-denial-sa
namespace: development
Explanation:
master1 $ vim psp.yaml
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: deny-policy
spec:
privileged: false # Don't allow privileged pods!
seLinux:
rule: RunAsAny
supplementalGroups:
rule: RunAsAny
runAsUser:
rule: RunAsAny
fsGroup:
rule: RunAsAny
volumes:
- '*'
master1 $ vim cr1.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: deny-access-role
rules:
- apiGroups: ['policy']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames:
- "deny-policy"
master1 $ k create sa psp-denial-sa -n development
master1 $ vim cb1.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: restrict-access-bing
roleRef:
kind: ClusterRole
name: deny-access-role
apiGroup: rbac.authorization.k8s.io
subjects:
# Authorize specific service accounts:
- kind: ServiceAccount
name: psp-denial-sa
namespace: development
master1 $ k apply -f psp.yaml
master1 $ k apply -f cr1.yaml
master1 $ k apply -f cb1.yaml