This page introduces the CIS Kubernetes Benchmark, provides an assessment, and explains what Google Distributed Cloud connected does to address the recommendations.
The CIS Benchmark
The Center for Internet Security (CIS) releases benchmarks for best practice security recommendations. The CIS Kubernetes Benchmark provides a set of recommendations for configuring Kubernetes to support a strong security posture. The Benchmark is tied to a specific Kubernetes release. The CIS Kubernetes Benchmark is written for the open source Kubernetes distribution and intended to be as universally applicable across distributions as possible.
Versions
The following table lists the versions of Distributed Cloud connected, Kubernetes, and the CIS Kubernetes Benchmark that were used to perform the assessment described in this document:
| Distributed Cloud connected version | Kubernetes version | CIS Kubernetes Benchmark version |
|---|---|---|
| 1.4.0 - Local Control Plane | 1.25 | 1.70 |
Accessing the Benchmark
The CIS Kubernetes Benchmark is available on the CIS website.
Recommendation levels
In the CIS Kubernetes Benchmark,
| Level | Description |
|---|---|
| Level 1 | Recommendations intend to: |
| Level 2 | Extends the Level 1 profile. Recommendations exhibit one or more of the following characteristics: |
Assessment status
An assessment status is included for every recommendation. The assessment status indicates whether the given recommendation can be automated or requires manual steps to implement. Both statuses are equally important and are determined and supported as defined below:
| Scoring | Description |
|---|---|
| Automated | Represents recommendations for which assessment of a technical control can be fully automated and validated to a pass/fail state. Recommendations will include the necessary information to implement automation. |
| Manual | Represents recommendations for which assessment of a technical control cannot be fully automated and requires all or some manual steps to validate that the configured state is set as expected. The expected state can vary depending on the environment. |
Status on Distributed Cloud connected local control plane clusters
| # | Recommendation | Level | Status |
|---|---|---|---|
| 1 | Control Plane Security Configuration | ||
| 1.1 | Control Plane Node Configuration Files | ||
| 1.1.1 | Ensure that the API server pod specification file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 1.1.2 | Ensure that the API server pod specification file ownership is set to root:root (Automated) |
L1 | Pass |
| 1.1.3 | Ensure that the controller manager pod specification file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 1.1.4 | Ensure that the controller manager pod specification file ownership is set to root:root (Automated) |
L1 | Pass |
| 1.1.5 | Ensure that the scheduler pod specification file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 1.1.6 | Ensure that the scheduler pod specification file ownership is set to root:root (Automated) |
L1 | Pass |
| 1.1.7 | Ensure that the etcd pod specification file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 1.1.8 | Ensure that the etcd pod specification file ownership is set to root:root (Automated) |
L1 | Pass |
| 1.1.9 | Ensure that the Container Network Interface file permissions are set to 644 or more restrictive (Manual) |
L1 | Equivalent Control |
| 1.1.10 | Ensure that the Container Network Interface file ownership is set to root:root (Manual) |
L1 | Pass |
| 1.1.11 | Ensure that the etcd data directory permissions are set to 700 or more restrictive (Automated) |
L1 | Equivalent Control |
| 1.1.12 | Ensure that the etcd data directory ownership is set to etcd:etcd (Automated) |
L1 | Equivalent Control |
| 1.1.13 | Ensure that the admin.conf file permissions are set to 600 or more restrictive (Automated) |
L1 | Pass |
| 1.1.14 | Ensure that the admin.conf file ownership is set to root:root (Automated) |
L1 | Pass |
| 1.1.15 | Ensure that the scheduler.conf file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 1.1.16 | Ensure that the scheduler.conf file ownership is set to root:root (Automated) |
L1 | Equivalent Control |
| 1.1.17 | Ensure that the controller-manager.conf file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 1.1.18 | Ensure that the controller-manager.conf file ownership is set to root:root (Automated) |
L1 | Equivalent Control |
| 1.1.19 | Ensure that the Kubernetes PKI directory and file ownership is set to root:root (Automated) |
L1 | Equivalent Control |
| 1.1.20 | Ensure that the Kubernetes PKI certificate file permissions are set to 644 or more restrictive (Manual) |
L1 | Equivalent Control |
| 1.1.21 | Ensure that the Kubernetes PKI key file permissions are set to 600 (Manual) |
L1 | Pass |
| 1.2 | API Server | ||
| 1.2.1 | Ensure that the --anonymous-auth argument is set to false (Manual) |
L1 | Pass |
| 1.2.2 | Ensure that the --token-auth-file parameter is not set (Automated) |
L1 | Pass |
| 1.2.3 | Ensure that the --DenyServiceExternalIPs is not set (Automated) |
L1 | Fail |
| 1.2.4 | Ensure that the --kubelet-client-certificate and --kubelet-client-key arguments are set as appropriate (Automated) |
L1 | Pass |
| 1.2.5 | Ensure that the --kubelet-certificate-authority argument is set as appropriate (Automated) |
L1 | Pass |
| 1.2.6 | Ensure that the --authorization-mode argument is not set to AlwaysAllow (Automated) |
L1 | Pass |
| 1.2.7 | Ensure that the --authorization-mode argument includes Node (Automated) |
L1 | Pass |
| 1.2.8 | Ensure that the --authorization-mode argument includes RBAC (Automated) |
L1 | Fail |
| 1.2.9 | Ensure that the admission control plugin EventRateLimit is set (Manual) | L1 | Pass |
| 1.2.10 | Ensure that the admission control plugin AlwaysAdmit is not set (Automated) | L1 | Pass |
| 1.2.11 | Ensure that the admission control plugin AlwaysPullImages is set (Manual) | L1 | Fail |
| 1.2.12 | Ensure that the admission control plugin SecurityContextDeny is set if PodSecurityPolicy is not used (Manual) | L1 | Warn |
| 1.2.13 | Ensure that the admission control plugin ServiceAccount is set (Automated) | L1 | Pass |
| 1.2.14 | Ensure that the admission control plugin NamespaceLifecycle is set (Automated) | L1 | Pass |
| 1.2.15 | Ensure that the admission control plugin NodeRestriction is set (Automated) | L1 | Pass |
| 1.2.16 | Ensure that the --secure-port argument is not set to 0 (Automated) |
L1 | Pass |
| 1.2.17 | Ensure that the --profiling argument is set to false (Automated) |
L1 | Pass |
| 1.2.18 | Ensure that the --audit-log-path argument is set (Automated) |
L1 | Fail |
| 1.2.19 | Ensure that the --audit-log-maxage argument is set to 30 or as appropriate (Automated) |
L1 | Fail |
| 1.2.20 | Ensure that the --audit-log-maxbackup argument is set to 10 or as appropriate (Automated) |
L1 | Fail |
| 1.2.21 | Ensure that the --audit-log-maxsize argument is set to 100 or as appropriate (Automated) |
L1 | Fail |
| 1.2.22 | Ensure that the --request-timeout argument is set as appropriate (Manual) |
L1 | Fail |
| 1.2.23 | Ensure that the --service-account-lookup argument is set to true (Automated) |
L1 | Pass |
| 1.2.24 | Ensure that the --service-account-key-file argument is set as appropriate (Automated) |
L1 | Pass |
| 1.2.25 | Ensure that the --etcd-certfile and --etcd-keyfile arguments are set as appropriate (Automated) |
L1 | Pass |
| 1.2.26 | Ensure that the --tls-cert-file and --tls-private-key-file arguments are set as appropriate (Automated) |
L1 | Pass |
| 1.2.27 | Ensure that the --client-ca-file argument is set as appropriate (Automated) |
L1 | Pass |
| 1.2.28 | Ensure that the --etcd-cafile argument is set as appropriate (Automated) |
L1 | Pass |
| 1.2.29 | Ensure that the --encryption-provider-config argument is set as appropriate (Manual) |
L1 | Pass |
| 1.2.30 | Ensure that encryption providers are appropriately configured (Manual) | L1 | Pass |
| 1.2.31 | Ensure that the API Server only makes use of Strong Cryptographic Ciphers (Manual) | L1 | Pass |
| 1.3 | Controller Manager | ||
| 1.3.1 | Ensure that the --terminated-pod-gc-threshold argument is set as appropriate (Manual) |
L1 | Pass |
| 1.3.2 | Ensure that the --profiling argument is set to false (Automated) |
L1 | Pass |
| 1.3.3 | Ensure that the --use-service-account-credentials argument is set to true (Automated) |
L1 | Pass |
| 1.3.4 | Ensure that the --service-account-private-key-file argument is set as appropriate (Automated) |
L1 | Pass |
| 1.3.5 | Ensure that the --root-ca-file argument is set as appropriate (Automated) |
L1 | Pass |
| 1.3.6 | Ensure that the RotateKubeletServerCertificate argument is set to true (Automated) | L2 | Pass |
| 1.3.7 | Ensure that the --bind-address argument is set to 127.0.0.1 (Automated) |
L1 | Pass |
| 1.4 | Scheduler | ||
| 1.4.1 | Ensure that the --profiling argument is set to false (Automated) |
L1 | Pass |
| 1.4.2 | Ensure that the --bind-address argument is set to 127.0.0.1 (Automated) |
L1 | Pass |
| 2 | ** etcd Node Configuration** |
||
| 2.1 | Ensure that the --cert-file and --key-file arguments are set as appropriate (Automated) |
L1 | Pass |
| 2.2 | Ensure that the --client-cert-auth argument is set to true (Automated) |
L1 | Pass |
| 2.3 | Ensure that the --auto-tls argument is not set to true (Automated) |
L1 | Pass |
| 2.4 | Ensure that the --peer-cert-file and --peer-key-file arguments are set as appropriate (Automated) |
L1 | Pass |
| 2.5 | Ensure that the --peer-client-cert-auth argument is set to true (Automated) |
L1 | Pass |
| 2.6 | Ensure that the --peer-auto-tls argument is not set to true (Automated) |
L1 | Pass |
| 2.7 | Ensure that a unique Certificate Authority is used for etcd (Manual) | L2 | Pass |
| 3 | Control Plane Configuration | ||
| 3.1 | Authentication and Authorization | ||
| 3.1.1 | Client certificate authentication should not be used for users (Manual) | L2 | Pass |
| 3.2 | Logging | ||
| 3.2.1 | Ensure that a minimal audit policy is created (Manual) | L1 | Pass |
| 3.2.2 | Ensure that the audit policy covers key security concerns (Manual) | L2 | Fail |
| 4 | Worker Node Security Configuration | ||
| 4.1 | Worker Node Configuration Files | ||
| 4.1.1 | Ensure that the kubelet service file permissions are set to 644 or more restrictive (Automated) |
L1 | Fail |
| 4.1.2 | Ensure that the kubelet service file ownership is set to root:root (Automated) |
L1 | Pass |
| 4.1.3 | If proxy kubeconfig file exists ensure permissions are set to 644 or more restrictive (Manual) |
L1 | Pass |
| 4.1.4 | If proxy kubeconfig file exists ensure ownership is set to root:root (Manual) |
L1 | Pass |
| 4.1.5 | Ensure that the --kubeconfig kubelet.conf file permissions are set to 644 or more restrictive (Automated) |
L1 | Pass |
| 4.1.6 | Ensure that the --kubeconfig kubelet.conf file ownership is set to root:root (Automated) |
L1 | Pass |
| 4.1.7 | Ensure that the certificate authorities file permissions are set to 644 or more restrictive (Manual) |
L1 | Fail |
| 4.1.8 | Ensure that the client certificate authorities file ownership is set to root:root (Manual) |
L1 | Pass |
| 4.1.9 | Ensure that the kubelet --config configuration file has permissions set to 644 or more restrictive (Automated) |
L1 | Fail |
| 4.1.10 | Ensure that the kubelet --config configuration file ownership is set to root:root (Automated) |
L1 | Pass |
| 4.2 | Kubelet | ||
| 4.2.1 | Ensure that the --anonymous-auth argument is set to false (Automated) |
L1 | Pass |
| 4.2.2 | Ensure that the --authorization-mode argument is not set to AlwaysAllow (Automated) |
L1 | Pass |
| 4.2.3 | Ensure that the --client-ca-file argument is set as appropriate (Automated) |
L1 | Pass |
| 4.2.4 | Ensure that the --read-only-port argument is set to 0 (Manual) |
L1 | Fail |
| 4.2.5 | Ensure that the --streaming-connection-idle-timeout argument is not set to 0 (Manual) |
L1 | Pass |
| 4.2.6 | Ensure that the --protect-kernel-defaults argument is set to true (Automated) |
L1 | Pass |
| 4.2.7 | Ensure that the --make-iptables-util-chains argument is set to true (Automated) |
L1 | Pass |
| 4.2.8 | Ensure that the --hostname-override argument is not set (Manual) |
L2 | Pass |
| 4.2.9 | Ensure that the --event-qps argument is set to 0 or a level which ensures appropriate event capture (Manual) |
L1 | Equivalent Control |
| 4.2.10 | Ensure that the --tls-cert-file and --tls-private-key-file arguments are set as appropriate (Manual) |
L1 | Pass |
| 4.2.11 | Ensure that the --rotate-certificates argument is not set to false (Automated) |
L1 | Pass |
| 4.2.12 | Verify that the RotateKubeletServerCertificate argument is set to true (Manual) | L1 | Pass |
| 4.2.13 | Ensure that the Kubelet only makes use of Strong Cryptographic Ciphers (Manual) | L1 | Fail |
Failures and equivalent controls for Distributed Cloud connected local control plane clusters
| # | Recommendation | Level | Status | Value | Justification |
|---|---|---|---|---|---|
| 1 | Control Plane Security Configuration | ||||
| 1.1.9 | Ensure that the Container Network Interface file permissions are set to 644 or more restrictive (Manual) |
L1 | Equivalent Control | 755 |
None. |
| 1.1.11 | Ensure that the etcd data directory permissions are set to 700 or more restrictive (Automated) |
L1 | Equivalent Control | 755 |
The etcd data directory has the default 755 permissions but its subdirectories use 700. |
| 1.1.12 | Ensure that the etcd data directory ownership is set to etcd:etcd (Automated) |
L1 | Equivalent Control | 2003:2003 |
The etcd data directory, /var/lib/etcd, is owned by 2003:2003 due to rootless control-plane for enhanced security. |
| 1.1.16 | Ensure that the scheduler.conf file ownership is set to root:root (Automated) |
L1 | Equivalent Control | 2002:2002 |
scheduler.conf is owned by 2002:2002 due to rootless control-plane for enhanced security. |
| 1.1.18 | Ensure that the controller-manager.conf file ownership is set to root:root (Automated) |
L1 | Equivalent Control | 2001:2001 |
controller-manager.conf is owned by 2001:2001 due to rootless control-plane for enhanced security. |
| 1.1.19 | Ensure that the Kubernetes PKI directory and file ownership is set to root:root (Automated) |
L1 | Equivalent Control | Varies | The PKI directory, /etc/kubernetes/pki, is owned by root:root; the files inside the directory have various owners. This is due to rootless control-plane for enhanced security. |
| 1.1.20 | Ensure that the Kubernetes PKI certificate file permissions are set to 644 or more restrictive (Manual) |
L1 | Equivalent Control | 644 |
This is due to rootless control-plane for enhanced security. |
| 1.2 | API Server | ||||
| 1.2.3 | Ensure that the --DenyServiceExternalIPs is not set (Automated) |
L1 | Fail | ||
| 1.2.9 | Ensure that the --authorization-mode argument includes RBAC (Automated) |
L1 | Fail | Event Rate Limit admission controller is a Kubernetes alpha feature. Google Distributed Cloud does not support non-GA features. | |
| 1.2.11 | Ensure that the admission control plugin AlwaysAdmit is not set (Automated) |
L1 | Fail | ||
| 1.2.12 | Ensure that the admission control plugin AlwaysPullImages is set (Manual) |
L1 | Fail | The AlwaysPullImages admission controller provides some protection for private registry images in non-cooperative multitenant clusters at the cost of making container registries single points of failure for creating new pods across the entire cluster. Distributed Cloud clusters do not enable the AlwaysPullImages admission controller, which leaves it up to cluster administrators to implement admission policy to make this tradeoff for themselves. |
|
| 1.2.18 | Ensure that the --audit-log-path argument is set (Automated) |
L1 | Fail | Distributed Cloud captures audit logs but does not use this flag for auditing. See Audit Logging for more information. | |
| 1.2.19 | Ensure that the --audit-log-maxage argument is set to 30 or as appropriate (Automated) |
L1 | Fail | Distributed Cloud captures audit logs but does not use this flag for auditing. See Audit Logging for more information. | |
| 1.2.20 | Ensure that the --audit-log-maxbackup argument is set to 10 or as appropriate (Automated) |
L1 | Fail | Distributed Cloud connected captures audit logs but does not use this flag for auditing. See Audit Logging for more information. | |
| 1.2.21 | Ensure that the --audit-log-maxsize argument is set to 100 or as appropriate (Automated) |
L1 | Fail | Distributed Cloud connected captures audit logs but does not use this flag for auditing. See Audit Logging for more information. | |
| 1.2.22 | Ensure that the --request-timeout argument is set as appropriate (Manual) |
L1 | Fail | Distributed Cloud connected captures audit logs but does not use this flag for auditing. See Audit Logging for more information. | |
| 3 | Control Plane Configuration | ||||
| 3.2.2 | Ensure that the audit policy covers key security concerns (Manual) | L2 | Fail | ||
| 4 | Worker Node Security Configuration | ||||
| 4.1.1 | Ensure that the kubelet service file permissions are set to 644 or more restrictive (Automated) |
L1 | Fail | 755 |
|
| 4.1.7 | Ensure that the certificate authorities file permissions are set to 644 or more restrictive (Manual) |
L1 | Fail | ||
| 4.1.9 | Ensure that the kubelet --config configuration file has permissions set to 644 or more restrictive (Automated) |
L1 | Fail | 644 |
|
| 4.2.4 | Ensure that the --read-only-port argument is set to 0 (Manual) |
L1 | Fail | Distributed Cloud connected clusters set the --read-only-port argument to 10255 for collecting kubelet metrics. |
|
| 4.2.9 | Ensure that the --event-qps argument is set to 0 or a level which ensures appropriate event capture (Manual) |
L1 | Equivalent Control | Distributed Cloud clusters manage kubelet server TLS using the –rotate-server-certificates flag. |
|
| 4.2.13 | Ensure that the Kubelet only makes use of Strong Cryptographic Ciphers (Manual) | L1 | Fail |
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Last updated 2024-12-04 UTC.