├── .gitignore ├── LICENSE ├── README.md ├── demos.md └── res ├── podasroot.yaml ├── podasusr.yaml └── podwithsa.yaml /.gitignore: -------------------------------------------------------------------------------- 1 | .DS_Store 2 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. 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[Building container images](#building-container-images) 4 | - [Running containers](#running-containers) 5 | - [Authentication and authorization](#authentication-and-authorization) 6 | - [Communication](#communication) 7 | - [Apps](#apps) 8 | - [Securing the control plane](#securing-the-control-plane) 9 | - [References](#references) 10 | 11 | ## Building container images 12 | 13 | Tooling: 14 | 15 | - https://docs.docker.com/docker-cloud/builds/image-scan/ 16 | - https://github.com/coreos/clair 17 | - https://www.open-scap.org/tools/ 18 | - https://www.aquasec.com/use-cases/continuous-image-assurance/ 19 | - https://neuvector.com/container-compliance-auditing-solutions/ 20 | - https://github.com/theupdateframework/notary 21 | - https://github.com/in-toto 22 | 23 | Further reading: 24 | 25 | - [Establishing Image Provenance and Security in Kubernetes](https://www.youtube.com/watch?v=zs-6YEUrJAM) 26 | - [Image Management & Mutability in Docker and Kubernetes](https://container-solutions.com/image-management-mutability-in-docker-and-kubernetes/) 27 | - [Container security considerations in a Kubernetes deployment](https://thenewstack.io/container-security-considerations-kubernetes-deployment/) 28 | - [Building Container Images Securely on Kubernetes](https://blog.jessfraz.com/post/building-container-images-securely-on-kubernetes/) 29 | - [The OpenShift Build Process](https://docs.openshift.com/container-platform/3.9/security/build_process.html) 30 | - [Introducing Grafeas: An open-source API to audit and govern your software supply chain](https://cloudplatform.googleblog.com/2017/10/introducing-grafeas-open-source-api-.html) 31 | 32 | ## Running containers 33 | 34 | Tooling: 35 | 36 | - https://github.com/aquasecurity/kube-bench 37 | - https://github.com/docker/docker-bench-security 38 | - https://sysdig.com/opensource/falco/ 39 | - https://kubesec.io/ 40 | - https://www.twistlock.com/ 41 | 42 | Further reading: 43 | 44 | - [Just say no to root (in containers)](https://opensource.com/article/18/3/just-say-no-root-containers) 45 | - Exploring Container Mechanisms Through the Story of a Syscall ([slides](https://schd.ws/hosted_files/kccnceu18/46/Exploring%20container%20mechanisms%20through%20the%20story%20of%20a%20syscall.pdf) | [video](https://www.youtube.com/watch?v=1Tl-NURLoq4)) 46 | - [Improving your Kubernetes Workload Security](https://www.youtube.com/watch?v=T_NxDXAdbfo) 47 | Container Isolation at Scale (Introducing gVisor) ([slides](https://schd.ws/hosted_files/kccnceu18/47/Container%20Isolation%20at%20Scale.pdf) | [video](https://www.youtube.com/watch?v=pWyJahTWa4I)) 48 | 49 | ## Authentication and authorization 50 | 51 | Tooling: 52 | 53 | - https://github.com/coreos/dex 54 | - https://github.com/liggitt/audit2rbac 55 | - https://github.com/heptio/authenticator 56 | 57 | Further reading: 58 | 59 | - Docs: [Authentication](https://kubernetes.io/docs/admin/authentication/), [Authorization](https://kubernetes.io/docs/admin/authorization/), [Controlling Access to the Kubernetes API](https://kubernetes.io/docs/reference/access-authn-authz/controlling-access/) 60 | - [Kubernetes deep dive: API Server – part 1](https://blog.openshift.com/kubernetes-deep-dive-api-server-part-1/) 61 | - [Certifik8s: All You Need to Know About Certificates in Kubernetes](https://www.youtube.com/watch?v=gXz4cq3PKdg) 62 | - [Kubernetes Auth and Access Control](https://www.youtube.com/watch?v=WvnXemaYQ50) 63 | - [Effective RBAC](https://www.youtube.com/watch?v=Nw1ymxcLIDI) 64 | - [Single Sign-On for Kubernetes: An Introduction](https://thenewstack.io/kubernetes-single-sign-one-less-identity/) 65 | - [Let's Encrypt, OAuth 2, and Kubernetes Ingress](https://eng.fromatob.com/post/2017/02/lets-encrypt-oauth-2-and-kubernetes-ingress/) 66 | 67 | 68 | ## Communication 69 | 70 | Tooling: 71 | 72 | - https://github.com/aporeto-inc/trireme-kubernetes 73 | - https://github.com/jetstack/cert-manager/ 74 | - https://spiffe.io/ 75 | - https://www.openpolicyagent.org/ 76 | 77 | Further reading: 78 | 79 | - Docs: [Network policies](https://kubernetes.io/docs/concepts/services-networking/network-policies/) 80 | - [How Kubernetes certificate authorities work](https://jvns.ca/blog/2017/08/05/how-kubernetes-certificates-work/) 81 | - [Securing Kubernetes Cluster Networking](https://ahmet.im/blog/kubernetes-network-policy/) 82 | - [Tutorials and Recipes for Kubernetes Network Policies feature](https://github.com/ahmetb/kubernetes-network-policy-recipes) 83 | - [Kubernetes Security Context and Kubernetes Network Policy](https://sysdig.com/blog/kubernetes-security-psp-network-policy/) 84 | - [Kubernetes Application Operator Basics](https://blog.openshift.com/kubernetes-application-operator-basics/) 85 | 86 | ## Apps 87 | 88 | Tooling: 89 | 90 | - https://github.com/kelseyhightower/konfd 91 | - https://github.com/hashicorp/vault-plugin-auth-kubernetes 92 | - https://github.com/bitnami-labs/sealed-secrets 93 | - https://github.com/shyiko/kubesec 94 | - https://github.com/weaveworks/flux 95 | 96 | Further reading: 97 | 98 | - Docs: [Secrets](https://kubernetes.io/docs/concepts/configuration/secret/), [Configure a Security Context for a Pod or Container](https://kubernetes.io/docs/tasks/configure-pod-container/security-context/), [Pod Security Policies](https://kubernetes.io/docs/concepts/policy/pod-security-policy/) 99 | - [Shipping in Pirate-Infested Waters: Practical Attack and Defense in Kubernetes](https://www.youtube.com/watch?v=ohTq0no0ZVU) 100 | - [Exploring container security: Isolation at different layers of the Kubernetes stack](https://cloudplatform.googleblog.com/2018/05/Exploring-container-security-Isolation-at-different-layers-of-the-Kubernetes-stack.html) 101 | - [Security Best Practices for Kubernetes Deployment](https://kubernetes.io/blog/2016/08/security-best-practices-kubernetes-deployment/) 102 | - [NIST Special Publication 800-190: Application Container Security Guide](https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-190.pdf) 103 | - [Kubernetes Security Best Practices](https://www.youtube.com/watch?v=pzAwTC8KYV8) 104 | - [Continuous Kubernetes Security](https://www.youtube.com/watch?v=YtrA7eauSSg) 105 | 106 | ## Securing the control plane 107 | 108 | Tooling: 109 | 110 | - https://github.com/bgeesaman/kubeatf 111 | - https://github.com/Shopify/kubeaudit 112 | - https://k8guard.github.io/ 113 | 114 | Further reading: 115 | 116 | - Docs: [Securing a Cluster](https://kubernetes.io/docs/tasks/administer-cluster/securing-a-cluster/), [Encrypting Secret Data at Rest](https://kubernetes.io/docs/tasks/administer-cluster/encrypt-data/), [Auditing](https://kubernetes.io/docs/tasks/debug-application-cluster/audit/) 117 | - [Securing Kubernetes components: kubelet, etcd and Docker registry](https://sysdig.com/blog/kubernetes-security-kubelet-etcd/) 118 | - [K8s security best practices](https://www.slideshare.net/SharonVendrov/k8s-security-best-practices-85961183) 119 | - [Kubernetes Security - Best Practice Guide](https://github.com/freach/kubernetes-security-best-practice) 120 | - [Lessons from the Cryptojacking Attack at Tesla](https://blog.redlock.io/cryptojacking-tesla) 121 | - [Hacking and Hardening Kubernetes Clusters by Example](https://www.youtube.com/watch?v=vTgQLzeBfRU) 122 | - [What Does “Production Ready” Really Mean for a Kubernetes Cluster](https://weave.works/blog/what-does-production-ready-really-mean-for-a-kubernetes-cluster) 123 | - [A Hacker's Guide to Kubernetes and the Cloud](https://www.youtube.com/watch?v=dxKpCO2dAy8) 124 | - [Kubernetes Container Clustering, Catastrophe](https://www.youtube.com/watch?v=b3qJwIttqqs) 125 | - [Hardening Kubernetes from Scratch](https://github.com/hardening-kubernetes/from-scratch) 126 | 127 | ## References 128 | 129 | Kubernetes resources related to security (v1.10): 130 | 131 | - [Namespace](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#namespace-v1-core) 132 | - [Secret](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#secret-v1-core) 133 | - [ResourceQuota](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#resourcequota-v1-core) 134 | - [ServiceAccount](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#serviceaccount-v1-core) 135 | - [Role](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#role-v1-rbac-authorization-k8s-io) / [ClusterRole](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#clusterrole-v1-rbac-authorization-k8s-io) 136 | - [RoleBinding](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#rolebinding-v1-rbac-authorization-k8s-io) / [ClusterRoleBinding](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#clusterrolebinding-v1-rbac-authorization-k8s-io) 137 | - [PodSecurityPolicy](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#podsecuritypolicy-v1beta1-extensions) 138 | - [NetworkPolicy](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.10/#networkpolicy-v1-networking-k8s-io) 139 | 140 | Useful `kubectl` commands: 141 | 142 | - `kubectl create secret` 143 | - `kubectl create serviceaccount` 144 | - `kubectl create role` 145 | - `kubectl create rolebinding` 146 | - `kubectl auth can-i` 147 | -------------------------------------------------------------------------------- /demos.md: -------------------------------------------------------------------------------- 1 | # Demos 2 | 3 | ```bash 4 | $ kubectl create ns demo 5 | ``` 6 | 7 | ## Running containers 8 | 9 | Creating two pods, one running as root the other as user with ID `1234`: 10 | 11 | ```bash 12 | $ kubectl -n=demo apply -f res/podasroot.yaml 13 | $ kubectl -n=demo apply -f res/podasusr.yaml 14 | $ minikube ssh 15 | $ ps -faux | grep sleep 16 | ``` 17 | 18 | ## Authentication & Authorization 19 | 20 | Accessing the API from pod: 21 | 22 | ```bash 23 | $ kubectl run -it --rm apiaccess \ 24 | --restart=Never --image=quay.io/mhausenblas/jump:0.2 25 | ls -al /var/run/secrets/kubernetes.io/serviceaccount/ 26 | export CURL_CA_BUNDLE=/var/run/secrets/kubernetes.io/serviceaccount/ca.crt 27 | APISERVERTOKEN=$(cat /var/run/secrets/kubernetes.io/serviceaccount/token) 28 | curl -H "Authorization: Bearer $APISERVERTOKEN" https://kubernetes.default 29 | ``` 30 | 31 | Create service account: 32 | 33 | ```bash 34 | $ kubectl -n=demo create serviceaccount mysa 35 | ``` 36 | 37 | Run pod with service account and explore contents: 38 | 39 | ```bash 40 | $ kubectl -n=demo apply -f res/podwithsa.yaml 41 | $ kubectl -n=demo get secret 42 | $ kubectl -n=demo describe secret mysa-token-d6tjw 43 | ``` 44 | 45 | Look into the pod how the service account info has been made available via a volume mount: 46 | 47 | ```bash 48 | $ kubectl -n=demo exec -it podwithsa -- sh 49 | cd /var/run/secrets/kubernetes.io/serviceaccount/ 50 | cat token 51 | ``` 52 | 53 | Also, check JWT token via https://jwt.io 54 | 55 | 56 | Next, create a role and rolebinding for being able to view and list pods: 57 | 58 | ```bash 59 | $ kubectl -n=demo create role podreader --verb=get --verb=list --resource=pods 60 | $ kubectl -n=demo get role/podreader -o=yaml 61 | 62 | $ kubectl -n=demo create rolebinding podreaderbinding --role=podreader --serviceaccount=demo:mysa --dry-run=true -o=yaml 63 | ``` 64 | 65 | ```bash 66 | $ kubectl -n=demo auth can-i list pods --as=system:serviceaccount:demo:mysa 67 | $ kubectl -n=demo auth can-i create pods --as=system:serviceaccount:demo:mysa 68 | ``` 69 | -------------------------------------------------------------------------------- /res/podasroot.yaml: -------------------------------------------------------------------------------- 1 | apiVersion: v1 2 | kind: Pod 3 | metadata: 4 | name: podasroot 5 | spec: 6 | containers: 7 | - name: shell 8 | image: alpine:3.7 9 | command: 10 | - "sh" 11 | - "-c" 12 | - "sleep 10000" 13 | -------------------------------------------------------------------------------- /res/podasusr.yaml: -------------------------------------------------------------------------------- 1 | apiVersion: v1 2 | kind: Pod 3 | metadata: 4 | name: podasusr 5 | spec: 6 | securityContext: 7 | runAsUser: 1234 8 | containers: 9 | - name: shell 10 | image: alpine:3.7 11 | command: 12 | - "sh" 13 | - "-c" 14 | - "sleep 10001" 15 | -------------------------------------------------------------------------------- /res/podwithsa.yaml: -------------------------------------------------------------------------------- 1 | apiVersion: v1 2 | kind: Pod 3 | metadata: 4 | name: podwithsa 5 | spec: 6 | serviceAccountName: mysa 7 | containers: 8 | - name: shell 9 | image: alpine:3.7 10 | command: 11 | - "sh" 12 | - "-c" 13 | - "sleep 10000" --------------------------------------------------------------------------------