10 KCSA questions with full explanations for every option, free to view on this page.
Kubernetes Cluster Component Security
Q1. What is the security risk of running the kubelet with `--read-only-port` enabled?
Reveal answer and explanations
AUnauthenticated clients can read sensitive pod information via the read-only port
Correct. The kubelet read-only port (default 10255) serves metrics and pod information without authentication, allowing any network-accessible client to gather intelligence about running pods and nodes.
Betcd encryption is automatically disabled
Incorrect. The read-only port does not affect etcd encryption settings.
CPod specification files cannot be read by authorized users
Incorrect. The read-only port allows authorized reading, but the security issue is lack of authentication.
DContainer logs are not encrypted in transit
Incorrect. The read-only port does not directly relate to log encryption.
Kubernetes Cluster Component Security
Q2. Which of the following is a key advantage of RBAC over ABAC in Kubernetes?
Reveal answer and explanations
ARBAC does not require authentication
Incorrect. Both RBAC and ABAC operate after authentication.
BABAC is the default authorization mode in modern Kubernetes versions
Incorrect. RBAC is the standard; ABAC is rarely used in production due to complexity.
CRBAC is simpler to understand and manage because it groups permissions into predefined roles
Correct. RBAC abstracts permissions into reusable roles (ClusterRole, Role) and bindings, making policies easier to understand and maintain at scale compared to ABAC's attribute-based matching.
DABAC provides better performance than RBAC
Incorrect. Performance differences between RBAC and ABAC are negligible; RBAC is favored for manageability.
Kubernetes Cluster Component Security
Q3. What is the purpose of kubelet client certificate authentication?
Reveal answer and explanations
ATo sign container images in the registry
Incorrect. Certificate authentication for kubelets does not sign container images.
BTo encrypt data stored in etcd
Incorrect. Kubelet client certificates do not encrypt etcd storage.
CTo authenticate end users connecting to the Kubernetes cluster
Incorrect. Kubelet certificates authenticate components to each other, not end users.
DTo verify that API server requests to the kubelet come from legitimate cluster components
Correct. Kubelet client certificate authentication ensures that only authorized components (like the API server) can communicate with the kubelet, preventing spoofed requests.
Kubernetes Cluster Component Security
Q4. You discover that etcd peers are communicating without mutual TLS authentication. What is the immediate security concern?
Reveal answer and explanations
AAll Secrets are automatically deleted
Incorrect. Secrets are not automatically deleted due to communication encryption issues.
BThe cluster data is exposed to man-in-the-middle attacks and unauthorized access to etcd data
Correct. Without mutual TLS between etcd peers, attackers on the network can intercept cluster state data, potentially leading to compromise of all cluster resources.
CThe API server becomes read-only
Incorrect. While etcd unavailability would stop the cluster, unencrypted communication doesn't make the API server read-only.
DPods cannot schedule on the affected nodes
Incorrect. Etcd peer communication issues would affect the entire cluster, not pod scheduling individually.
Kubernetes Cluster Component Security
Q5. Which of the following best describes kube-proxy's role in cluster security?
Reveal answer and explanations
AIt encrypts all pod-to-pod communication
Incorrect. kube-proxy does not encrypt pod-to-pod communication; that requires a service mesh or NetworkPolicies.
BIt maintains network rules for routing traffic to Service endpoints
Correct. kube-proxy creates and maintains network rules (via iptables, IPVS, or other mechanisms) to route traffic to Services, making it critical for proper network isolation and traffic control.
CIt authenticates users and authorizes API requests
Incorrect. Authentication and authorization are the API server's responsibility.
DIt proxies external HTTP traffic to Services
Incorrect. While kube-proxy is involved in routing, it is not specifically an HTTP proxy.
Kubernetes Cluster Component Security
Q6. A new worker node is joining your cluster without pre-provisioned kubelet client certificates. What does kubelet TLS bootstrapping provide?
Reveal answer and explanations
ATo encrypt the container runtime communication protocol
Incorrect. Container runtime communication is configured separately from TLS bootstrapping.
BTo allow kubelets to request client certificates from the API server without pre-provisioned credentials
Correct. TLS bootstrapping allows new nodes to join the cluster securely by using a bootstrap token to request a client certificate from the CA, eliminating the need to pre-distribute credentials.
CTo enable automatic cluster scaling based on resource utilization
Incorrect. Cluster autoscaling uses different mechanisms than TLS bootstrapping.
DTo authenticate users logging into worker nodes via SSH
Incorrect. SSH authentication is a separate concern from kubelet certificate provisioning.
Kubernetes Cluster Component Security
Q7. What is a security implication of running the container runtime without proper access controls?
Reveal answer and explanations
AThe API server cannot authenticate Service accounts
Incorrect. Container runtime access does not prevent API server authentication.
BKubernetes Secrets are automatically exposed in pod logs
Incorrect. Secrets exposure in logs is a separate concern from container runtime access.
CUnauthorized users can interact directly with the container runtime to run privileged containers or access host resources
Correct. The container runtime is a critical security boundary. Unrestricted access allows bypassing Kubernetes security controls to run arbitrary containers with escalated privileges.
Detcd communication becomes unencrypted
Incorrect. Container runtime access does not affect etcd encryption.
Kubernetes Cluster Component Security
Q8. A misconfigured kubelet is listening on port 10250 with client certificate authentication disabled. Which of the following is a realistic attack scenario?
Reveal answer and explanations
AAttackers can read pod logs and execute commands inside containers via the kubelet API
Correct. An unauthenticated kubelet API allows remote code execution, container escape, and data exfiltration from pods.
BAttackers can revoke user API server access tokens
Incorrect. Token management is the responsibility of the API server, not the kubelet.
CAttackers can change the admission webhook URL
Incorrect. Admission webhooks are configured in the API server, not the kubelet.
DAttackers can modify the control plane configuration
Incorrect. The control plane configuration is protected by the API server, not the kubelet.
Kubernetes Cluster Component Security
Q9. How does setting proper kubelet authorization rules enhance cluster security?
Reveal answer and explanations
AIt prevents container images from being pulled from public registries
Incorrect. Kubelet authorization does not control image registry access.
BIt automatically encrypts all Secrets at the container runtime level
Incorrect. Kubelet authorization does not handle Secret encryption.
CIt disables all networking between pods
Incorrect. Kubelet authorization does not control pod networking.
DIt restricts which operations the kubelet can perform based on incoming requests
Correct. Kubelet authorization enforces which API operations (like pod creation, log access, exec) are allowed, preventing privilege escalation and lateral movement.
Kubernetes Cluster Component Security
Q10. A security audit finds the read-only kubelet port (10255) exposed on worker nodes in a production cluster. What risk does this present?
Reveal answer and explanations
ADisables all network policies on the node
Incorrect. The read-only port does not affect network policy enforcement.
BAllows anyone to make changes to the kubelet configuration
Incorrect. The read-only port does not permit modifications; it is read-only.
CDirectly enables privilege escalation to root
Incorrect. While reconnaissance can lead to privilege escalation, the port itself does not directly enable it.
DProvides read-only access to pod and node information without authentication, enabling reconnaissance for further attacks
Correct. The unauthenticated read-only port exposes sensitive information like running pods, their configuration, and node details, which attackers can use for reconnaissance.
These questions are written against the current KCSA curriculum — not scraped exam dumps. The full KCSA library here has 120 questions; the broader platform covers the rest of the Golden Kubestronaut path.