- CIS Kubernetes Benchmark v1.5 - Rancher v2.3.5 with Kubernetes v1.15
- 概述
- 测试控制方法
- 1 Master Node Security Configuration
- 1.1 Master Node Configuration Files
- 1.1.1 Ensure that the API server pod specification file permissions are set to
644
or more restrictive (Scored) - 1.1.2 Ensure that the API server pod specification file ownership is set to
root:root
(Scored) - 1.1.3 Ensure that the controller manager pod specification file permissions are set to
644
or more restrictive (Scored) - 1.1.4 Ensure that the controller manager pod specification file ownership is set to
root:root
(Scored) - 1.1.5 Ensure that the scheduler pod specification file permissions are set to
644
or more restrictive (Scored) - 1.1.6 Ensure that the scheduler pod specification file ownership is set to
root:root
(Scored) - 1.1.7 Ensure that the etcd pod specification file permissions are set to
644
or more restrictive (Scored) - 1.1.8 Ensure that the etcd pod specification file ownership is set to
root:root
(Scored) - 1.1.11 Ensure that the etcd data directory permissions are set to
700
or more restrictive (Scored) - 1.1.12 Ensure that the etcd data directory ownership is set to
etcd:etcd
(Scored) - 1.1.13 Ensure that the
admin.conf
file permissions are set to644
or more restrictive (Scored) - 1.1.14 Ensure that the admin.conf file ownership is set to
root:root
(Scored) - 1.1.15 Ensure that the
scheduler.conf
file permissions are set to644
or more restrictive (Scored) - 1.1.16 Ensure that the
scheduler.conf
file ownership is set toroot:root
(Scored) - 1.1.17 Ensure that the
controller-manager.conf
file permissions are set to644
or more restrictive (Scored) - 1.1.18 Ensure that the
controller-manager.conf
file ownership is set toroot:root
(Scored) - 1.1.19 Ensure that the Kubernetes PKI directory and file ownership is set to
root:root
(Scored) - 1.1.20 Ensure that the Kubernetes PKI certificate file permissions are set to
644
or more restrictive (Scored) - 1.1.21 Ensure that the Kubernetes PKI key file permissions are set to
600
(Scored)
- 1.1.1 Ensure that the API server pod specification file permissions are set to
- 1.2 API Server
- 1.2.2 Ensure that the
--basic-auth-file
argument is not set (Scored) - 1.2.3 Ensure that the
--token-auth-file
parameter is not set (Scored) - 1.2.4 Ensure that the
--kubelet-https
argument is set to true (Scored) - 1.2.5 Ensure that the
--kubelet-client-certificate
and--kubelet-client-key
arguments are set as appropriate (Scored) - 1.2.6 Ensure that the
--kubelet-certificate-authority
argument is set as appropriate (Scored) - 1.2.7 Ensure that the
--authorization-mode
argument is not set toAlwaysAllow
(Scored) - 1.2.8 Ensure that the
--authorization-mode
argument includesNode
(Scored) - 1.2.9 Ensure that the
--authorization-mode
argument includesRBAC
(Scored) - 1.2.11 Ensure that the admission control plugin
AlwaysAdmit
is not set (Scored) - 1.2.14 Ensure that the admission control plugin
ServiceAccount
is set (Scored) - 1.2.15 Ensure that the admission control plugin
NamespaceLifecycle
is set (Scored) - 1.2.16 Ensure that the admission control plugin
PodSecurityPolicy
is set (Scored) - 1.2.17 Ensure that the admission control plugin
NodeRestriction
is set (Scored) - 1.2.18 Ensure that the
--insecure-bind-address
argument is not set (Scored) - 1.2.19 Ensure that the
--insecure-port
argument is set to0
(Scored) - 1.2.20 Ensure that the
--secure-port
argument is not set to0
(Scored) - 1.2.21 Ensure that the
--profiling
argument is set tofalse
(Scored) - 1.2.22 Ensure that the
--audit-log-path
argument is set (Scored) - 1.2.23 Ensure that the
--audit-log-maxage
argument is set to30
or as appropriate (Scored) - 1.2.24 Ensure that the
--audit-log-maxbackup
argument is set to10
or as appropriate (Scored) - 1.2.25 Ensure that the
--audit-log-maxsize
argument is set to100
or as appropriate (Scored) - 1.2.26 Ensure that the
--request-timeout
argument is set as appropriate (Scored) - 1.2.27 Ensure that the
--service-account-lookup
argument is set totrue
(Scored) - 1.2.28 Ensure that the
--service-account-key-file
argument is set as appropriate (Scored) - 1.2.29 Ensure that the
--etcd-certfile
and--etcd-keyfile
arguments are set as appropriate (Scored) - 1.2.30 Ensure that the
--tls-cert-file
and--tls-private-key-file
arguments are set as appropriate (Scored) - 1.2.31 Ensure that the
--client-ca-file
argument is set as appropriate (Scored) - 1.2.32 Ensure that the
--etcd-cafile
argument is set as appropriate (Scored) - 1.2.33 Ensure that the
--encryption-provider-config
argument is set as appropriate (Scored) - 1.2.34 Ensure that encryption providers are appropriately configured (Scored)
- 1.2.2 Ensure that the
- 1.3 Controller Manager
- 1.3.1 Ensure that the
--terminated-pod-gc-threshold
argument is set as appropriate (Scored) - 1.3.2 Ensure that the
--profiling
argument is set to false (Scored) - 1.3.3 Ensure that the
--use-service-account-credentials
argument is set totrue
(Scored) - 1.3.4 Ensure that the
--service-account-private-key-file
argument is set as appropriate (Scored) - 1.3.5 Ensure that the
--root-ca-file
argument is set as appropriate (Scored) - 1.3.6 Ensure that the
RotateKubeletServerCertificate
argument is set totrue
(Scored) - 1.3.7 Ensure that the
--bind-address argument
is set to127.0.0.1
(Scored)
- 1.3.1 Ensure that the
- 1.4 Scheduler
- 1.1 Master Node Configuration Files
- 2 Etcd Node Configuration
- 2 Etcd Node Configuration Files
- 2.1 Ensure that the
--cert-file
and--key-file
arguments are set as appropriate (Scored) - 2.2 Ensure that the
--client-cert-auth
argument is set totrue
(Scored) - 2.3 Ensure that the
--auto-tls
argument is not set totrue
(Scored) - 2.4 Ensure that the
--peer-cert-file
and--peer-key-file
arguments are set as appropriate (Scored) - 2.5 Ensure that the
--peer-client-cert-auth
argument is set totrue
(Scored) - 2.6 Ensure that the
--peer-auto-tls
argument is not set totrue
(Scored)
- 2.1 Ensure that the
- 2 Etcd Node Configuration Files
- 3 Control Plane Configuration
- 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 (Scored) - 4.1.2 Ensure that the kubelet service file ownership is set to
root:root
(Scored) - 4.1.3 Ensure that the proxy kubeconfig file permissions are set to
644
or more restrictive (Scored) - 4.1.4 Ensure that the proxy kubeconfig file ownership is set to
root:root
(Scored) - 4.1.5 Ensure that the kubelet.conf file permissions are set to
644
or more restrictive (Scored) - 4.1.6 Ensure that the kubelet.conf file ownership is set to
root:root
(Scored) - 4.1.7 Ensure that the certificate authorities file permissions are set to
644
or more restrictive (Scored) - 4.1.8 Ensure that the client certificate authorities file ownership is set to
root:root
(Scored) - 4.1.9 Ensure that the kubelet configuration file has permissions set to
644
or more restrictive (Scored) - 4.1.10 Ensure that the kubelet configuration file ownership is set to
root:root
(Scored)
- 4.1.1 Ensure that the kubelet service file permissions are set to
- 4.2 Kubelet
- 4.2.1 Ensure that the
--anonymous-auth argument
is set to false (Scored) - 4.2.2 Ensure that the
--authorization-mode
argument is not set toAlwaysAllow
(Scored) - 4.2.3 Ensure that the
--client-ca-file
argument is set as appropriate (Scored) - 4.2.4 Ensure that the
--read-only-port
argument is set to0
(Scored) - 4.2.5 Ensure that the
--streaming-connection-idle-timeout
argument is not set to0
(Scored) - 4.2.6 Ensure that the
--protect-kernel-defaults
argument is set totrue
(Scored) - 4.2.7 Ensure that the
--make-iptables-util-chains
argument is set totrue
(Scored) - 4.2.10 Ensure that the
--tls-cert-file
and--tls-private-key-file
arguments are set as appropriate (Scored) - 4.2.11 Ensure that the
--rotate-certificates
argument is not set tofalse
(Scored) - 4.2.12 Ensure that the
RotateKubeletServerCertificate
argument is set totrue
(Scored)
- 4.2.1 Ensure that the
- 4.1 Worker Node Configuration Files
- 5 Kubernetes Policies
- 5.1 RBAC and Service Accounts
- 5.2 Pod Security Policies
- 5.2.2 Minimize the admission of containers wishing to share the host process ID namespace (Scored)
- 5.2.3 Minimize the admission of containers wishing to share the host IPC namespace (Scored)
- 5.2.4 Minimize the admission of containers wishing to share the host network namespace (Scored)
- 5.2.5 Minimize the admission of containers with
allowPrivilegeEscalation
(Scored)
- 5.3 Network Policies and CNI
- 5.6 General Policies
title: 自测指南 - v2.3.5 description: 本文档是对 Rancher v2.3.5 安全加固指南的补充。加固指南提供了用于加固 Rancher 的生产环境集群的指南,该基准自测指南旨在帮助您针对安全基准中的每个控制,来评估加固集群的安全级别。本指南将逐步介绍各种控制,并提供更新的示例命令以审核 Rancher 创建的集群中的合规性。此文档的适用人群是:Rancher 运维人员、安全团队、审核员和决策者。 keywords:
- rancher
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- rancher中文文档
- rancher官网
- rancher文档
- Rancher
- rancher 中文
- rancher 中文文档
- rancher cn
- 安全
- CIS自测指南
- 自测指南 - v2.3.5
CIS Kubernetes Benchmark v1.5 - Rancher v2.3.5 with Kubernetes v1.15
概述
本文档是对 Rancher v2.3.5 安全加固指南的补充。加固指南提供了用于加固 Rancher 的生产环境集群的指南,该基准自测指南旨在帮助您针对安全基准中的每个控制,来评估加固集群的安全级别。本指南将逐步介绍各种控制,并提供更新的示例命令以审核 Rancher 创建的集群中的合规性。此文档的适用人群是:Rancher 运维人员、安全团队、审核员和决策者。
加固指南旨在与特定版本的安全加固指南,CIS Kubernetes Benchmark,Kubernetes 和 Rancher 一起使用:
自测指南版本 | Rancher 版本 | 安全加固指南版本 | Kubernetes 版本 | CIS Benchmark 版本 |
---|---|---|---|---|
自测指南 v2.3.5 | Rancher v2.3.5 | 安全加固指南 v2.3.5 | Kubernetes v1.15 | Benchmark v1.5 |
由于 Rancher 和 RKE 以容器的方式安装 Kubernetes,因此 CIS Kubernetes Benchmark 中的许多控制验证检查均不适用,完成 CIS 扫描后,这些检测对应的结论是Not Applicable
(不适用)。
有关每个审核的更多详细信息,包括测试失败的原因和补救措施,您可以参考 CIS Kubernetes Benchmark v1.5 的相应部分。登录CISecurity.org后,可以下载基准测试。
测试控制方法
Rancher 和 RKE 通过 Docker 容器安装 Kubernetes 服务。配置在初始化时通过给容器传递参数的方式设置,而不是通过配置文件定义。
如果控制审核与原始 CIS 基准不同,则将提供 Rancher Labs 特定的审核命令以进行测试。执行测试时,您将需要访问所有三个 RKE 角色的主机上的 Docker 命令行。这些命令还利用了jq和kubectl(使用有效的 kubeconfig 文件)来测试和评估测试结果。
1 Master Node Security Configuration
1.1 Master Node Configuration Files
1.1.1 Ensure that the API server pod specification file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the API server. All configuration is passed in as arguments at container run time.
1.1.2 Ensure that the API server pod specification file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the API server. All configuration is passed in as arguments at container run time.
1.1.3 Ensure that the controller manager pod specification file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the controller manager. All configuration is passed in as arguments at container run time.
1.1.4 Ensure that the controller manager pod specification file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the controller manager. All configuration is passed in as arguments at container run time.
1.1.5 Ensure that the scheduler pod specification file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the scheduler. All configuration is passed in as arguments at container run time.
1.1.6 Ensure that the scheduler pod specification file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the scheduler. All configuration is passed in as arguments at container run time.
1.1.7 Ensure that the etcd pod specification file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for etcd. All configuration is passed in as arguments at container run time.
1.1.8 Ensure that the etcd pod specification file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for etcd. All configuration is passed in as arguments at container run time.
1.1.11 Ensure that the etcd data directory permissions are set to 700
or more restrictive (Scored)
Result: PASS
Remediation:
On the etcd server node, get the etcd data directory, passed as an argument --data-dir
,
from the below command:
ps -ef | grep etcd
Run the below command (based on the etcd data directory found above). For example,
chmod 700 /var/lib/etcd
Audit Script: 1.1.11.sh
#!/bin/bash -e
etcd_bin=${1}
test_dir=$(ps -ef | grep ${etcd_bin} | grep -- --data-dir | sed 's%.*data-dir[= ]\([^ ]*\).*%\1%')
docker inspect etcd | jq -r '.[].HostConfig.Binds[]' | grep "${test_dir}" | cut -d ":" -f 1 | xargs stat -c %a
Audit Execution:
./1.1.11.sh etcd
Expected result:
'700' is equal to '700'
1.1.12 Ensure that the etcd data directory ownership is set to etcd:etcd
(Scored)
Result: PASS
Remediation:
On the etcd server node, get the etcd data directory, passed as an argument --data-dir
,
from the below command:
ps -ef | grep etcd
Run the below command (based on the etcd data directory found above). For example,
chown etcd:etcd /var/lib/etcd
Audit Script: 1.1.12.sh
#!/bin/bash -e
etcd_bin=${1}
test_dir=$(ps -ef | grep ${etcd_bin} | grep -- --data-dir | sed 's%.*data-dir[= ]\([^ ]*\).*%\1%')
docker inspect etcd | jq -r '.[].HostConfig.Binds[]' | grep "${test_dir}" | cut -d ":" -f 1 | xargs stat -c %U:%G
Audit Execution:
./1.1.12.sh etcd
Expected result:
'etcd:etcd' is present
1.1.13 Ensure that the admin.conf
file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation:
RKE does not store the kubernetes default kubeconfig credentials file on the nodes. It’s presented to user where RKE is run.
We recommend that this kube_config_cluster.yml
file be kept in secure store.
1.1.14 Ensure that the admin.conf file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation:
RKE does not store the kubernetes default kubeconfig credentials file on the nodes. It’s presented to user where RKE is run.
We recommend that this kube_config_cluster.yml
file be kept in secure store.
1.1.15 Ensure that the scheduler.conf
file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the scheduler. All configuration is passed in as arguments at container run time.
1.1.16 Ensure that the scheduler.conf
file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the scheduler. All configuration is passed in as arguments at container run time.
1.1.17 Ensure that the controller-manager.conf
file permissions are set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the controller manager. All configuration is passed in as arguments at container run time.
1.1.18 Ensure that the controller-manager.conf
file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the controller manager. All configuration is passed in as arguments at container run time.
1.1.19 Ensure that the Kubernetes PKI directory and file ownership is set to root:root
(Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the master node. For example,
chown -R root:root /etc/kubernetes/ssl
Audit:
stat -c %U:%G /etc/kubernetes/ssl
Expected result:
'root:root' is present
1.1.20 Ensure that the Kubernetes PKI certificate file permissions are set to 644
or more restrictive (Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the master node. For example,
chmod -R 644 /etc/kubernetes/ssl
Audit Script: check_files_permissions.sh
#!/usr/bin/env bash
# This script is used to ensure the file permissions are set to 644 or
# more restrictive for all files in a given directory or a wildcard
# selection of files
#
# inputs:
# $1 = /full/path/to/directory or /path/to/fileswithpattern
# ex: !(*key).pem
#
# $2 (optional) = permission (ex: 600)
#
# outputs:
# true/false
# Turn on "extended glob" for use of '!' in wildcard
shopt -s extglob
# Turn off history to avoid surprises when using '!'
set -H
USER_INPUT=$1
if [[ "${USER_INPUT}" == "" ]]; then
echo "false"
exit
fi
if [[ -d ${USER_INPUT} ]]; then
PATTERN="${USER_INPUT}/*"
else
PATTERN="${USER_INPUT}"
fi
PERMISSION=""
if [[ "$2" != "" ]]; then
PERMISSION=$2
fi
FILES_PERMISSIONS=$(stat -c %n\ %a ${PATTERN})
while read -r fileInfo; do
p=$(echo ${fileInfo} | cut -d' ' -f2)
if [[ "${PERMISSION}" != "" ]]; then
if [[ "$p" != "${PERMISSION}" ]]; then
echo "false"
exit
fi
else
if [[ "$p" != "644" && "$p" != "640" && "$p" != "600" ]]; then
echo "false"
exit
fi
fi
done <<< "${FILES_PERMISSIONS}"
echo "true"
exit
Audit Execution:
./check_files_permissions.sh '/etc/kubernetes/ssl/*.pem'
Expected result:
'true' is present
1.1.21 Ensure that the Kubernetes PKI key file permissions are set to 600
(Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the master node. For example,
chmod -R 600 /etc/kubernetes/ssl/certs/serverca
Audit Script: 1.1.21.sh
#!/bin/bash -e
check_dir=${1:-/etc/kubernetes/ssl}
for file in $(find ${check_dir} -name "*key.pem"); do
file_permission=$(stat -c %a ${file})
if [[ "${file_permission}" == "600" ]]; then
continue
else
echo "FAIL: ${file} ${file_permission}"
exit 1
fi
done
echo "pass"
Audit Execution:
./1.1.21.sh /etc/kubernetes/ssl
Expected result:
'pass' is present
1.2 API Server
1.2.2 Ensure that the --basic-auth-file
argument is not set (Scored)
Result: PASS
Remediation:
Follow the documentation and configure alternate mechanisms for authentication. Then,
edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and remove the --basic-auth-file=<filename>
parameter.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--basic-auth-file' is not present
1.2.3 Ensure that the --token-auth-file
parameter is not set (Scored)
Result: PASS
Remediation:
Follow the documentation and configure alternate mechanisms for authentication. Then,
edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and remove the --token-auth-file=<filename>
parameter.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--token-auth-file' is not present
1.2.4 Ensure that the --kubelet-https
argument is set to true (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and remove the --kubelet-https
parameter.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--kubelet-https' is present OR '--kubelet-https' is not present
1.2.5 Ensure that the --kubelet-client-certificate
and --kubelet-client-key
arguments are set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and set up the TLS connection between the
apiserver and kubelets. Then, edit API server pod specification file
/etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the
kubelet client certificate and key parameters as below.
--kubelet-client-certificate=<path/to/client-certificate-file>
--kubelet-client-key=<path/to/client-key-file>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--kubelet-client-certificate' is present AND '--kubelet-client-key' is present
1.2.6 Ensure that the --kubelet-certificate-authority
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and setup the TLS connection between
the apiserver and kubelets. Then, edit the API server pod specification file
/etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the
--kubelet-certificate-authority
parameter to the path to the cert file for the certificate authority.
--kubelet-certificate-authority=<ca-string>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--kubelet-certificate-authority' is present
1.2.7 Ensure that the --authorization-mode
argument is not set to AlwaysAllow
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --authorization-mode
parameter to values other than AlwaysAllow
.
One such example could be as below.
--authorization-mode=RBAC
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'Node,RBAC' not have 'AlwaysAllow'
1.2.8 Ensure that the --authorization-mode
argument includes Node
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --authorization-mode
parameter to a value that includes Node
.
--authorization-mode=Node,RBAC
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'Node,RBAC' has 'Node'
1.2.9 Ensure that the --authorization-mode
argument includes RBAC
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --authorization-mode
parameter to a value that includes RBAC,
for example:
--authorization-mode=Node,RBAC
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'Node,RBAC' has 'RBAC'
1.2.11 Ensure that the admission control plugin AlwaysAdmit
is not set (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and either remove the --enable-admission-plugins
parameter, or set it to a
value that does not include AlwaysAdmit
.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota,NodeRestriction,Priority,TaintNodesByCondition,PersistentVolumeClaimResize,PodSecurityPolicy,EventRateLimit' not have 'AlwaysAdmit' OR '--enable-admission-plugins' is not present
1.2.14 Ensure that the admission control plugin ServiceAccount
is set (Scored)
Result: PASS
Remediation:
Follow the documentation and create ServiceAccount objects as per your environment.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and ensure that the --disable-admission-plugins
parameter is set to a
value that does not include ServiceAccount
.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota,NodeRestriction,Priority,TaintNodesByCondition,PersistentVolumeClaimResize,PodSecurityPolicy,EventRateLimit' has 'ServiceAccount' OR '--enable-admission-plugins' is not present
1.2.15 Ensure that the admission control plugin NamespaceLifecycle
is set (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --disable-admission-plugins
parameter to
ensure it does not include NamespaceLifecycle
.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--disable-admission-plugins' is present OR '--disable-admission-plugins' is not present
1.2.16 Ensure that the admission control plugin PodSecurityPolicy
is set (Scored)
Result: PASS
Remediation:
Follow the documentation and create Pod Security Policy objects as per your environment.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --enable-admission-plugins
parameter to a
value that includes PodSecurityPolicy
:
--enable-admission-plugins=...,PodSecurityPolicy,...
Then restart the API Server.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota,NodeRestriction,Priority,TaintNodesByCondition,PersistentVolumeClaimResize,PodSecurityPolicy,EventRateLimit' has 'PodSecurityPolicy'
1.2.17 Ensure that the admission control plugin NodeRestriction
is set (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and configure NodeRestriction
plug-in on kubelets.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --enable-admission-plugins
parameter to a
value that includes NodeRestriction
.
--enable-admission-plugins=...,NodeRestriction,...
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota,NodeRestriction,Priority,TaintNodesByCondition,PersistentVolumeClaimResize,PodSecurityPolicy,EventRateLimit' has 'NodeRestriction'
1.2.18 Ensure that the --insecure-bind-address
argument is not set (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and remove the --insecure-bind-address
parameter.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--insecure-bind-address' is not present
1.2.19 Ensure that the --insecure-port
argument is set to 0
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the below parameter.
--insecure-port=0
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'0' is equal to '0'
1.2.20 Ensure that the --secure-port
argument is not set to 0
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and either remove the --secure-port
parameter or
set it to a different (non-zero) desired port.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
6443 is greater than 0 OR '--secure-port' is not present
1.2.21 Ensure that the --profiling
argument is set to false
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the below parameter.
--profiling=false
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'false' is equal to 'false'
1.2.22 Ensure that the --audit-log-path
argument is set (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --audit-log-path
parameter to a suitable path and
file where you would like audit logs to be written, for example:
--audit-log-path=/var/log/apiserver/audit.log
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--audit-log-path' is present
1.2.23 Ensure that the --audit-log-maxage
argument is set to 30
or as appropriate (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --audit-log-maxage
parameter to 30
or as an appropriate number of days:
--audit-log-maxage=30
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
30 is greater or equal to 30
1.2.24 Ensure that the --audit-log-maxbackup
argument is set to 10
or as appropriate (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --audit-log-maxbackup
parameter to 10
or to an appropriate
value.
--audit-log-maxbackup=10
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
10 is greater or equal to 10
1.2.25 Ensure that the --audit-log-maxsize
argument is set to 100
or as appropriate (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --audit-log-maxsize
parameter to an appropriate size in MB.
For example, to set it as 100
MB:
--audit-log-maxsize=100
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
100 is greater or equal to 100
1.2.26 Ensure that the --request-timeout
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
and set the below parameter as appropriate and if needed.
For example,
--request-timeout=300s
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--request-timeout' is not present OR '--request-timeout' is present
1.2.27 Ensure that the --service-account-lookup
argument is set to true
(Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the below parameter.
--service-account-lookup=true
Alternatively, you can delete the --service-account-lookup
parameter from this file so
that the default takes effect.
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--service-account-lookup' is not present OR 'true' is equal to 'true'
1.2.28 Ensure that the --service-account-key-file
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --service-account-key-file
parameter
to the public key file for service accounts:
`--service-account-key-file=<filename>`
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--service-account-key-file' is present
1.2.29 Ensure that the --etcd-certfile
and --etcd-keyfile
arguments are set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and set up the TLS connection between the apiserver and etcd.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the etcd certificate and key file parameters.
--etcd-certfile=<path/to/client-certificate-file>
--etcd-keyfile=<path/to/client-key-file>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--etcd-certfile' is present AND '--etcd-keyfile' is present
1.2.30 Ensure that the --tls-cert-file
and --tls-private-key-file
arguments are set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and set up the TLS connection on the apiserver.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the TLS certificate and private key file parameters.
--tls-cert-file=<path/to/tls-certificate-file>
--tls-private-key-file=<path/to/tls-key-file>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--tls-cert-file' is present AND '--tls-private-key-file' is present
1.2.31 Ensure that the --client-ca-file
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and set up the TLS connection on the apiserver.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the client certificate authority file.
--client-ca-file=<path/to/client-ca-file>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--client-ca-file' is present
1.2.32 Ensure that the --etcd-cafile
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and set up the TLS connection between the apiserver and etcd.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the etcd certificate authority file parameter.
--etcd-cafile=<path/to/ca-file>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--etcd-cafile' is present
1.2.33 Ensure that the --encryption-provider-config
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and configure a EncryptionConfig file.
Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml
on the master node and set the --encryption-provider-config
parameter to the path of that file:
--encryption-provider-config=</path/to/EncryptionConfig/File>
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'--encryption-provider-config' is present
1.2.34 Ensure that encryption providers are appropriately configured (Scored)
Result: PASS
Remediation:
Follow the Kubernetes documentation and configure a EncryptionConfig
file.
In this file, choose aescbc, kms or secretbox as the encryption provider.
Audit Script: 1.2.34.sh
#!/bin/bash -e
check_file=${1}
grep -q -E 'aescbc|kms|secretbox' ${check_file}
if [ $? -eq 0 ]; then
echo "--pass"
exit 0
else
echo "fail: encryption provider found in ${check_file}"
exit 1
fi
Audit Execution:
./1.2.34.sh /etc/kubernetes/ssl/encryption.yaml
Expected result:
'--pass' is present
1.3 Controller Manager
1.3.1 Ensure that the --terminated-pod-gc-threshold
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node and set the --terminated-pod-gc-threshold
to an appropriate threshold,
for example:
--terminated-pod-gc-threshold=10
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'--terminated-pod-gc-threshold' is present
1.3.2 Ensure that the --profiling
argument is set to false (Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node and set the below parameter.
--profiling=false
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'false' is equal to 'false'
1.3.3 Ensure that the --use-service-account-credentials
argument is set to true
(Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node to set the below parameter.
--use-service-account-credentials=true
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'true' is not equal to 'false'
1.3.4 Ensure that the --service-account-private-key-file
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node and set the --service-account-private-key-file
parameter
to the private key file for service accounts.
`--service-account-private-key-file=<filename>`
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'--service-account-private-key-file' is present
1.3.5 Ensure that the --root-ca-file
argument is set as appropriate (Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node and set the --root-ca-file
parameter to the certificate bundle file`.
--root-ca-file=<path/to/file>
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'--root-ca-file' is present
1.3.6 Ensure that the RotateKubeletServerCertificate
argument is set to true
(Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node and set the --feature-gates
parameter to include RotateKubeletServerCertificate=true
.
--feature-gates=RotateKubeletServerCertificate=true
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'RotateKubeletServerCertificate=true' is equal to 'RotateKubeletServerCertificate=true'
1.3.7 Ensure that the --bind-address argument
is set to 127.0.0.1
(Scored)
Result: PASS
Remediation:
Edit the Controller Manager pod specification file /etc/kubernetes/manifests/kube-controller-manager.yaml
on the master node and ensure the correct value for the --bind-address
parameter.
Audit:
/bin/ps -ef | grep kube-controller-manager | grep -v grep
Expected result:
'--bind-address' is present OR '--bind-address' is not present
1.4 Scheduler
1.4.1 Ensure that the --profiling
argument is set to false
(Scored)
Result: PASS
Remediation:
Edit the Scheduler pod specification file /etc/kubernetes/manifests/kube-scheduler.yaml
file
on the master node and set the below parameter.
--profiling=false
Audit:
/bin/ps -ef | grep kube-scheduler | grep -v grep
Expected result:
'false' is equal to 'false'
1.4.2 Ensure that the --bind-address
argument is set to 127.0.0.1
(Scored)
Result: PASS
Remediation:
Edit the Scheduler pod specification file /etc/kubernetes/manifests/kube-scheduler.yaml
on the master node and ensure the correct value for the --bind-address
parameter.
Audit:
/bin/ps -ef | grep kube-scheduler | grep -v grep
Expected result:
'--bind-address' is present OR '--bind-address' is not present
2 Etcd Node Configuration
2 Etcd Node Configuration Files
2.1 Ensure that the --cert-file
and --key-file
arguments are set as appropriate (Scored)
Result: PASS
Remediation:
Follow the etcd service documentation and configure TLS encryption.
Then, edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
on the master node and set the below parameters.
--cert-file=</path/to/ca-file>
--key-file=</path/to/key-file>
Audit:
/bin/ps -ef | /bin/grep etcd | /bin/grep -v grep
Expected result:
'--cert-file' is present AND '--key-file' is present
2.2 Ensure that the --client-cert-auth
argument is set to true
(Scored)
Result: PASS
Remediation:
Edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
on the master
node and set the below parameter.
--client-cert-auth="true"
Audit:
/bin/ps -ef | /bin/grep etcd | /bin/grep -v grep
Expected result:
'true' is equal to 'true'
2.3 Ensure that the --auto-tls
argument is not set to true
(Scored)
Result: PASS
Remediation:
Edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
on the master
node and either remove the --auto-tls
parameter or set it to false
.
--auto-tls=false
Audit:
/bin/ps -ef | /bin/grep etcd | /bin/grep -v grep
Expected result:
'--auto-tls' is not present OR '--auto-tls' is not present
2.4 Ensure that the --peer-cert-file
and --peer-key-file
arguments are set as appropriate (Scored)
Result: PASS
Remediation:
Follow the etcd service documentation and configure peer TLS encryption as appropriate
for your etcd cluster. Then, edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
on the
master node and set the below parameters.
--peer-client-file=</path/to/peer-cert-file>
--peer-key-file=</path/to/peer-key-file>
Audit:
/bin/ps -ef | /bin/grep etcd | /bin/grep -v grep
Expected result:
'--peer-cert-file' is present AND '--peer-key-file' is present
2.5 Ensure that the --peer-client-cert-auth
argument is set to true
(Scored)
Result: PASS
Remediation:
Edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
on the master
node and set the below parameter.
--peer-client-cert-auth=true
Audit:
/bin/ps -ef | /bin/grep etcd | /bin/grep -v grep
Expected result:
'true' is equal to 'true'
2.6 Ensure that the --peer-auto-tls
argument is not set to true
(Scored)
Result: PASS
Remediation:
Edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
on the master
node and either remove the --peer-auto-tls
parameter or set it to false
.
--peer-auto-tls=false
Audit:
/bin/ps -ef | /bin/grep etcd | /bin/grep -v grep
Expected result:
'--peer-auto-tls' is not present OR '--peer-auto-tls' is present
3 Control Plane Configuration
3.2 Logging
3.2.1 Ensure that a minimal audit policy is created (Scored)
Result: PASS
Remediation: Create an audit policy file for your cluster.
Audit Script: 3.2.1.sh
#!/bin/bash -e
api_server_bin=${1}
/bin/ps -ef | /bin/grep ${api_server_bin} | /bin/grep -v ${0} | /bin/grep -v grep
Audit Execution:
./3.2.1.sh kube-apiserver
Expected result:
'--audit-policy-file' is present
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 (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the kubelet service. All configuration is passed in as arguments at container run time.
4.1.2 Ensure that the kubelet service file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the kubelet service. All configuration is passed in as arguments at container run time.
4.1.3 Ensure that the proxy kubeconfig file permissions are set to 644
or more restrictive (Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the each worker node. For example,
chmod 644 /etc/kubernetes/ssl/kubecfg-kube-proxy.yaml
Audit:
/bin/sh -c 'if test -e /etc/kubernetes/ssl/kubecfg-kube-proxy.yaml; then stat -c %a /etc/kubernetes/ssl/kubecfg-kube-proxy.yaml; fi'
Expected result:
'644' is present OR '640' is present OR '600' is equal to '600' OR '444' is present OR '440' is present OR '400' is present OR '000' is present
4.1.4 Ensure that the proxy kubeconfig file ownership is set to root:root
(Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the each worker node. For example,
chown root:root /etc/kubernetes/ssl/kubecfg-kube-proxy.yaml
Audit:
/bin/sh -c 'if test -e /etc/kubernetes/ssl/kubecfg-kube-proxy.yaml; then stat -c %U:%G /etc/kubernetes/ssl/kubecfg-kube-proxy.yaml; fi'
Expected result:
'root:root' is present
4.1.5 Ensure that the kubelet.conf file permissions are set to 644
or more restrictive (Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the each worker node. For example,
chmod 644 /etc/kubernetes/ssl/kubecfg-kube-node.yaml
Audit:
/bin/sh -c 'if test -e /etc/kubernetes/ssl/kubecfg-kube-node.yaml; then stat -c %a /etc/kubernetes/ssl/kubecfg-kube-node.yaml; fi'
Expected result:
'644' is present OR '640' is present OR '600' is equal to '600' OR '444' is present OR '440' is present OR '400' is present OR '000' is present
4.1.6 Ensure that the kubelet.conf file ownership is set to root:root
(Scored)
Result: PASS
Remediation: Run the below command (based on the file location on your system) on the each worker node. For example,
chown root:root /etc/kubernetes/ssl/kubecfg-kube-node.yaml
Audit:
/bin/sh -c 'if test -e /etc/kubernetes/ssl/kubecfg-kube-node.yaml; then stat -c %U:%G /etc/kubernetes/ssl/kubecfg-kube-node.yaml; fi'
Expected result:
'root:root' is equal to 'root:root'
4.1.7 Ensure that the certificate authorities file permissions are set to 644
or more restrictive (Scored)
Result: PASS
Remediation: Run the following command to modify the file permissions of the
`--client-ca-file chmod 644 <filename>`
Audit:
stat -c %a /etc/kubernetes/ssl/kube-ca.pem
Expected result:
'644' is equal to '644' OR '640' is present OR '600' is present
4.1.8 Ensure that the client certificate authorities file ownership is set to root:root
(Scored)
Result: PASS
Remediation:
Run the following command to modify the ownership of the --client-ca-file
.
chown root:root `<filename>`
Audit:
/bin/sh -c 'if test -e /etc/kubernetes/ssl/kube-ca.pem; then stat -c %U:%G /etc/kubernetes/ssl/kube-ca.pem; fi'
Expected result:
'root:root' is equal to 'root:root'
4.1.9 Ensure that the kubelet configuration file has permissions set to 644
or more restrictive (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the kubelet service. All configuration is passed in as arguments at container run time.
4.1.10 Ensure that the kubelet configuration file ownership is set to root:root
(Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the kubelet service. All configuration is passed in as arguments at container run time.
4.2 Kubelet
4.2.1 Ensure that the --anonymous-auth argument
is set to false (Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set authentication: anonymous
: enabled to
false
.
If using executable arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
set the below parameter in KUBELET_SYSTEM_PODS_ARGS
variable.
--anonymous-auth=false
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'false' is equal to 'false'
4.2.2 Ensure that the --authorization-mode
argument is not set to AlwaysAllow
(Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set authorization: mode
to Webhook
. If
using executable arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
set the below parameter in KUBELET_AUTHZ_ARGS
variable.
--authorization-mode=Webhook
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'Webhook' not have 'AlwaysAllow'
4.2.3 Ensure that the --client-ca-file
argument is set as appropriate (Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set authentication: x509
: clientCAFile
to
the location of the client CA file.
If using command line arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
set the below parameter in KUBELET_AUTHZ_ARGS
variable.
--client-ca-file=<path/to/client-ca-file>
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'--client-ca-file' is present
4.2.4 Ensure that the --read-only-port
argument is set to 0
(Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set readOnlyPort
to 0
.
If using command line arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
set the below parameter in KUBELET_SYSTEM_PODS_ARGS
variable.
--read-only-port=0
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'0' is equal to '0'
4.2.5 Ensure that the --streaming-connection-idle-timeout
argument is not set to 0
(Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set streamingConnectionIdleTimeout
to a
value other than 0
.
If using command line arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
set the below parameter in KUBELET_SYSTEM_PODS_ARGS
variable.
--streaming-connection-idle-timeout=5m
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'30m' is not equal to '0' OR '--streaming-connection-idle-timeout' is not present
4.2.6 Ensure that the --protect-kernel-defaults
argument is set to true
(Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set protectKernelDefaults
: true
.
If using command line arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
set the below parameter in KUBELET_SYSTEM_PODS_ARGS
variable.
--protect-kernel-defaults=true
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'true' is equal to 'true'
4.2.7 Ensure that the --make-iptables-util-chains
argument is set to true
(Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to set makeIPTablesUtilChains
: true
.
If using command line arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
remove the --make-iptables-util-chains
argument from the
KUBELET_SYSTEM_PODS_ARGS
variable.
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'true' is equal to 'true' OR '--make-iptables-util-chains' is not present
4.2.10 Ensure that the --tls-cert-file
and --tls-private-key-file
arguments are set as appropriate (Scored)
Result: Not Applicable
Remediation: RKE doesn’t require or maintain a configuration file for the kubelet service. All configuration is passed in as arguments at container run time.
4.2.11 Ensure that the --rotate-certificates
argument is not set to false
(Scored)
Result: PASS
Remediation:
If using a Kubelet config file, edit the file to add the line rotateCertificates
: true
or
remove it altogether to use the default value.
If using command line arguments, edit the kubelet service file
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and
remove --rotate-certificates=false
argument from the KUBELET_CERTIFICATE_ARGS
variable.
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'--rotate-certificates' is present OR '--rotate-certificates' is not present
4.2.12 Ensure that the RotateKubeletServerCertificate
argument is set to true
(Scored)
Result: PASS
Remediation:
Edit the kubelet service file /etc/systemd/system/kubelet.service.d/10-kubeadm.conf
on each worker node and set the below parameter in KUBELET_CERTIFICATE_ARGS
variable.
--feature-gates=RotateKubeletServerCertificate=true
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'true' is equal to 'true'
5 Kubernetes Policies
5.1 RBAC and Service Accounts
5.1.5 Ensure that default service accounts are not actively used. (Scored)
Result: PASS
Remediation: Create explicit service accounts wherever a Kubernetes workload requires specific access to the Kubernetes API server. Modify the configuration of each default service account to include this value
automountServiceAccountToken: false
Audit Script: 5.1.5.sh
#!/bin/bash
export KUBECONFIG=${KUBECONFIG:-/root/.kube/config}
kubectl version > /dev/null
if [ $? -ne 0 ]; then
echo "fail: kubectl failed"
exit 1
fi
accounts="$(kubectl --kubeconfig=${KUBECONFIG} get serviceaccounts -A -o json | jq -r '.items[] | select(.metadata.name=="default") | select((.automountServiceAccountToken == null) or (.automountServiceAccountToken == true)) | "fail \(.metadata.name) \(.metadata.namespace)"')"
if [[ "${accounts}" != "" ]]; then
echo "fail: automountServiceAccountToken not false for accounts: ${accounts}"
exit 1
fi
default_binding="$(kubectl get rolebindings,clusterrolebindings -A -o json | jq -r '.items[] | select(.subjects[].kind=="ServiceAccount" and .subjects[].name=="default" and .metadata.name=="default").metadata.uid' | wc -l)"
if [[ "${default_binding}" -gt 0 ]]; then
echo "fail: default service accounts have non default bindings"
exit 1
fi
echo "--pass"
exit 0
Audit Execution:
./5.1.5.sh
Expected result:
'--pass' is present
5.2 Pod Security Policies
5.2.2 Minimize the admission of containers wishing to share the host process ID namespace (Scored)
Result: PASS
Remediation:
Create a PSP as described in the Kubernetes documentation, ensuring that the
.spec.hostPID
field is omitted or set to false
.
Audit:
kubectl --kubeconfig=/root/.kube/config get psp -o json | jq .items[] | jq -r 'select((.spec.hostPID == null) or (.spec.hostPID == false))' | jq .metadata.name | wc -l | xargs -I {} echo '--count={}'
Expected result:
1 is greater than 0
5.2.3 Minimize the admission of containers wishing to share the host IPC namespace (Scored)
Result: PASS
Remediation:
Create a PSP as described in the Kubernetes documentation, ensuring that the
.spec.hostIPC
field is omitted or set to false
.
Audit:
kubectl --kubeconfig=/root/.kube/config get psp -o json | jq .items[] | jq -r 'select((.spec.hostIPC == null) or (.spec.hostIPC == false))' | jq .metadata.name | wc -l | xargs -I {} echo '--count={}'
Expected result:
1 is greater than 0
5.2.4 Minimize the admission of containers wishing to share the host network namespace (Scored)
Result: PASS
Remediation:
Create a PSP as described in the Kubernetes documentation, ensuring that the
.spec.hostNetwork
field is omitted or set to false
.
Audit:
kubectl --kubeconfig=/root/.kube/config get psp -o json | jq .items[] | jq -r 'select((.spec.hostNetwork == null) or (.spec.hostNetwork == false))' | jq .metadata.name | wc -l | xargs -I {} echo '--count={}'
Expected result:
1 is greater than 0
5.2.5 Minimize the admission of containers with allowPrivilegeEscalation
(Scored)
Result: PASS
Remediation:
Create a PSP as described in the Kubernetes documentation, ensuring that the
.spec.allowPrivilegeEscalation
field is omitted or set to false
.
Audit:
kubectl --kubeconfig=/root/.kube/config get psp -o json | jq .items[] | jq -r 'select((.spec.allowPrivilegeEscalation == null) or (.spec.allowPrivilegeEscalation == false))' | jq .metadata.name | wc -l | xargs -I {} echo '--count={}'
Expected result:
1 is greater than 0
5.3 Network Policies and CNI
5.3.2 Ensure that all Namespaces have Network Policies defined (Scored)
Result: PASS
Remediation:
Follow the documentation and create NetworkPolicy
objects as you need them.
Audit Script: 5.3.2.sh
#!/bin/bash -e
export KUBECONFIG=${KUBECONFIG:-"/root/.kube/config"}
kubectl version > /dev/null
if [ $? -ne 0 ]; then
echo "fail: kubectl failed"
exit 1
fi
for namespace in $(kubectl get namespaces -o custom-columns=NAME:.metadata.name --no-headers); do
policy_count=$(kubectl get networkpolicy -n ${namespace} -o json | jq '.items | length')
if [ ${policy_count} -eq 0 ]; then
echo "fail: ${namespace}"
exit 1
fi
done
echo "pass"
Audit Execution:
./5.3.2.sh
Expected result:
'pass' is present
5.6 General Policies
5.6.4 The default namespace should not be used (Scored)
Result: PASS
Remediation: Ensure that namespaces are created to allow for appropriate segregation of Kubernetes resources and that all new resources are created in a specific namespace.
Audit Script: 5.6.4.sh
#!/bin/bash -e
export KUBECONFIG=${KUBECONFIG:-/root/.kube/config}
kubectl version > /dev/null
if [[ $? -gt 0 ]]; then
echo "fail: kubectl failed"
exit 1
fi
default_resources=$(kubectl get all -o json | jq --compact-output '.items[] | select((.kind == "Service") and (.metadata.name == "kubernetes") and (.metadata.namespace == "default") | not)' | wc -l)
echo "--count=${default_resources}"
Audit Execution:
./5.6.4.sh
Expected result:
'0' is equal to '0'