# CIS Benchmarks ### 1. 介绍 Kube-Bench是一款针对Kubernete的安全检测工具，从本质上来说，Kube-Bench是一个基于Go开发的应用程序，它可以帮助研究人员对部署的Kubernete进行安全检测，安全检测原则遵循[CIS Kubernetes Benchmark](https://www.cisecurity.org/benchmark/kubernetes/)。\ 测试规则需要通过YAML文件进行配置，因此我们可以轻松更新该工具的测试规则。 ![](https://img-blog.csdnimg.cn/20210422113251111.png?shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGloYWhhbGVsZWhlaGU=,size_16,color_FFFFFF,t_70) ![](https://img-blog.csdnimg.cn/20210422113309512.png?shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGloYWhhbGVsZWhlaGU=,size_16,color_FFFFFF,t_70) ![](https://img-blog.csdnimg.cn/20210422113415853.png?shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGloYWhhbGVsZWhlaGU=,size_16,color_FFFFFF,t_70) ### 2. 本地测试 ``` wget https://github.com/aquasecurity/kube-bench/releases/download/v0.4.0/kube-bench_0.4.0_linux_amd64.tar.gz tar -zxvf kube-bench_0.4.0_linux_amd64.tar.gz mv kube-bench /usr/bin/ ``` ``` kube-bench --config-dir `pwd`/cfg --config `pwd`/cfg/config.yaml master kube-bench --config-dir /data/software/kube-bench/cfg --config /data/software/kube-bench/cfg/config.yaml node ``` ### 3. 容器测试 ![在这里插入图片描述](https://img-blog.csdnimg.cn/20210422154146136.png?shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGloYWhhbGVsZWhlaGU=,size_16,color_FFFFFF,t_70) 参考链接：\ \\ 检查master节点的指标内容 ``` root@master:~/cks/metadata# kubectl get nodes NAME STATUS ROLES AGE VERSION master Ready control-plane,master 93d v1.20.1 node1 Ready 93d v1.20.1 node2 Ready 93d v1.20.1 root@master:~/cks/metadata# docker run --pid=host -v /etc:/etc:ro -v /var:/var:ro -t aquasec/kube-bench:latest master --version 1.20 Unable to find image 'aquasec/kube-bench:latest' locally latest: Pulling from aquasec/kube-bench 801bfaa63ef2: Pull complete b6310d2303a3: Pulling fs layer 4fb7d152903c: Download complete c8ea24332a01: Downloading c02463f95f5e: Download complete 763038f5a72b: Download complete 64bce6c8fa58: Download complete latest: Pulling from aquasec/kube-bench 801bfaa63ef2: Pull complete b6310d2303a3: Pull complete 4fb7d152903c: Pull complete c8ea24332a01: Pull complete c02463f95f5e: Pull complete 763038f5a72b: Pull complete 64bce6c8fa58: Pull complete Digest: sha256:bf9394a3ab84ebe9065a3f0256196f4257e73dad620ccab2f844fbc2f5e7969c Status: Downloaded newer image for aquasec/kube-bench:latest [INFO] 1 Master Node Security Configuration [INFO] 1.1 Master Node Configuration Files [PASS] 1.1.1 Ensure that the API server pod specification file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.2 Ensure that the API server pod specification file ownership is set to root:root (Automated) [PASS] 1.1.3 Ensure that the controller manager pod specification file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.4 Ensure that the controller manager pod specification file ownership is set to root:root (Automated) [PASS] 1.1.5 Ensure that the scheduler pod specification file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.6 Ensure that the scheduler pod specification file ownership is set to root:root (Automated) [PASS] 1.1.7 Ensure that the etcd pod specification file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.8 Ensure that the etcd pod specification file ownership is set to root:root (Automated) [WARN] 1.1.9 Ensure that the Container Network Interface file permissions are set to 644 or more restrictive (Manual) [WARN] 1.1.10 Ensure that the Container Network Interface file ownership is set to root:root (Manual) [PASS] 1.1.11 Ensure that the etcd data directory permissions are set to 700 or more restrictive (Automated) [FAIL] 1.1.12 Ensure that the etcd data directory ownership is set to etcd:etcd (Automated) [PASS] 1.1.13 Ensure that the admin.conf file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.14 Ensure that the admin.conf file ownership is set to root:root (Automated) [PASS] 1.1.15 Ensure that the scheduler.conf file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.16 Ensure that the scheduler.conf file ownership is set to root:root (Automated) [PASS] 1.1.17 Ensure that the controller-manager.conf file permissions are set to 644 or more restrictive (Automated) [PASS] 1.1.18 Ensure that the controller-manager.conf file ownership is set to root:root (Automated) [PASS] 1.1.19 Ensure that the Kubernetes PKI directory and file ownership is set to root:root (Automated) [PASS] 1.1.20 Ensure that the Kubernetes PKI certificate file permissions are set to 644 or more restrictive (Manual) [PASS] 1.1.21 Ensure that the Kubernetes PKI key file permissions are set to 600 (Manual) [INFO] 1.2 API Server [WARN] 1.2.1 Ensure that the --anonymous-auth argument is set to false (Manual) [PASS] 1.2.2 Ensure that the --basic-auth-file argument is not set (Automated) [PASS] 1.2.3 Ensure that the --token-auth-file parameter is not set (Automated) [PASS] 1.2.4 Ensure that the --kubelet-https argument is set to true (Automated) [PASS] 1.2.5 Ensure that the --kubelet-client-certificate and --kubelet-client-key arguments are set as appropriate (Automated) [FAIL] 1.2.6 Ensure that the --kubelet-certificate-authority argument is set as appropriate (Automated) [PASS] 1.2.7 Ensure that the --authorization-mode argument is not set to AlwaysAllow (Automated) [PASS] 1.2.8 Ensure that the --authorization-mode argument includes Node (Automated) [PASS] 1.2.9 Ensure that the --authorization-mode argument includes RBAC (Automated) [WARN] 1.2.10 Ensure that the admission control plugin EventRateLimit is set (Manual) [PASS] 1.2.11 Ensure that the admission control plugin AlwaysAdmit is not set (Automated) [WARN] 1.2.12 Ensure that the admission control plugin AlwaysPullImages is set (Manual) [WARN] 1.2.13 Ensure that the admission control plugin SecurityContextDeny is set if PodSecurityPolicy is not used (Manual) [PASS] 1.2.14 Ensure that the admission control plugin ServiceAccount is set (Automated) [PASS] 1.2.15 Ensure that the admission control plugin NamespaceLifecycle is set (Automated) [FAIL] 1.2.16 Ensure that the admission control plugin PodSecurityPolicy is set (Automated) [PASS] 1.2.17 Ensure that the admission control plugin NodeRestriction is set (Automated) [PASS] 1.2.18 Ensure that the --insecure-bind-address argument is not set (Automated) [PASS] 1.2.19 Ensure that the --insecure-port argument is set to 0 (Automated) [PASS] 1.2.20 Ensure that the --secure-port argument is not set to 0 (Automated) [FAIL] 1.2.21 Ensure that the --profiling argument is set to false (Automated) [FAIL] 1.2.22 Ensure that the --audit-log-path argument is set (Automated) [FAIL] 1.2.23 Ensure that the --audit-log-maxage argument is set to 30 or as appropriate (Automated) [FAIL] 1.2.24 Ensure that the --audit-log-maxbackup argument is set to 10 or as appropriate (Automated) [FAIL] 1.2.25 Ensure that the --audit-log-maxsize argument is set to 100 or as appropriate (Automated) [PASS] 1.2.26 Ensure that the --request-timeout argument is set as appropriate (Automated) [PASS] 1.2.27 Ensure that the --service-account-lookup argument is set to true (Automated) [PASS] 1.2.28 Ensure that the --service-account-key-file argument is set as appropriate (Automated) [PASS] 1.2.29 Ensure that the --etcd-certfile and --etcd-keyfile arguments are set as appropriate (Automated) [PASS] 1.2.30 Ensure that the --tls-cert-file and --tls-private-key-file arguments are set as appropriate (Automated) [PASS] 1.2.31 Ensure that the --client-ca-file argument is set as appropriate (Automated) [PASS] 1.2.32 Ensure that the --etcd-cafile argument is set as appropriate (Automated) [WARN] 1.2.33 Ensure that the --encryption-provider-config argument is set as appropriate (Manual) [WARN] 1.2.34 Ensure that encryption providers are appropriately configured (Manual) [WARN] 1.2.35 Ensure that the API Server only makes use of Strong Cryptographic Ciphers (Manual) [INFO] 1.3 Controller Manager [WARN] 1.3.1 Ensure that the --terminated-pod-gc-threshold argument is set as appropriate (Manual) [FAIL] 1.3.2 Ensure that the --profiling argument is set to false (Automated) [PASS] 1.3.3 Ensure that the --use-service-account-credentials argument is set to true (Automated) [PASS] 1.3.4 Ensure that the --service-account-private-key-file argument is set as appropriate (Automated) [PASS] 1.3.5 Ensure that the --root-ca-file argument is set as appropriate (Automated) [PASS] 1.3.6 Ensure that the RotateKubeletServerCertificate argument is set to true (Automated) [PASS] 1.3.7 Ensure that the --bind-address argument is set to 127.0.0.1 (Automated) [INFO] 1.4 Scheduler [FAIL] 1.4.1 Ensure that the --profiling argument is set to false (Automated) [PASS] 1.4.2 Ensure that the --bind-address argument is set to 127.0.0.1 (Automated) == Remediations master == 1.1.9 Run the below command (based on the file location on your system) on the master node. For example, chmod 644 1.1.10 Run the below command (based on the file location on your system) on the master node. For example, chown root:root 1.1.12 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 1.2.1 Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the below parameter. --anonymous-auth=false 1.2.6 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= 1.2.10 Follow the Kubernetes documentation and set the desired limits in a configuration file. Then, edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml and set the below parameters. --enable-admission-plugins=...,EventRateLimit,... --admission-control-config-file= 1.2.12 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 include AlwaysPullImages. --enable-admission-plugins=...,AlwaysPullImages,... 1.2.13 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 include SecurityContextDeny, unless PodSecurityPolicy is already in place. --enable-admission-plugins=...,SecurityContextDeny,... 1.2.16 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. 1.2.21 Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the below parameter. --profiling=false 1.2.22 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 1.2.23 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 1.2.24 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 1.2.25 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 1.2.33 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= 1.2.34 Follow the Kubernetes documentation and configure a EncryptionConfig file. In this file, choose aescbc, kms or secretbox as the encryption provider. 1.2.35 Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the below parameter. --tls-cipher-suites=TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,TLS_ECDHE_RSA_WITH_AES_128_GCM _SHA256,TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,TLS_ECDHE_RSA_WITH_AES_256_GCM _SHA384,TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,TLS_ECDHE_ECDSA_WITH_AES_256_GCM _SHA384 1.3.1 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 1.3.2 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 1.4.1 Edit the Scheduler pod specification file /etc/kubernetes/manifests/kube-scheduler.yaml file on the master node and set the below parameter. --profiling=false == Summary master == 45 checks PASS 10 checks FAIL #10个错误 10 checks WARN 0 checks INFO == Summary total == 45 checks PASS 10 checks FAIL 10 checks WARN 0 checks INFO ``` 修改其中一个错误，借助`CIS_Kubernetes_Benchmark_v1.6.0.pdf`搜索\ 链接：\ 提取码：r6vn ![在这里插入图片描述](https://img-blog.csdnimg.cn/20210422162210278.png?shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpeGloYWhhbGVsZWhlaGU=,size_16,color_FFFFFF,t_70) ``` root@master:~/cks/metadata# useradd etcd root@master:~/cks/metadata# chown etcd:etcd /var/lib/etcd ``` 再次检查运行 ``` root@master:~/cks/metadata# docker run --pid=host -v /etc:/etc:ro -v /var:/var:ro -t aquasec/kube-bench:latest master --version 1.20 ............#检查通过 [PASS] 1.1.12 Ensure that the etcd data directory ownership is set to etcd:etcd (Automated) ........... == Summary total == 46 checks PASS 9 checks FAIL #比上次少了一个检查失败的指标 10 checks WARN 0 checks INFO ``` 如果要检查node节点的指标\ 执行 ``` root@master:~/cks/metadata# docker run --pid=host -v /etc:/etc:ro -v /var:/var:ro -t aquasec/kube-bench:latest node --version 1.20 ``` {% hint style="info" %} **注意事项**： * `Kube-Bench`尽可能地实现了`CIS Kubernetes Benchmark`，如果`kube bench`没有正确执行安全基准测试。 * Kubernete版本和CIS基准测试版本之间没有一对一的映射。，以查看基准测试的不同版本包含哪些Kubernetes版本。 * `Kube-Bench`无法检查受管集群的主节点，例如GKE、EKS和AKS，因为`Kube-Bench`不能访问这些节点。不过，`Kube-Bench`在这些环境中仍然可以检查worker节点配置。 {% endhint %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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