Olá a todos.
Gostaria de compartilhar minha experiência de aprovação no exame Certified Kubernetes Security (CKS) da Linux Foundation . Este exame, como você pode imaginar, testa nossa capacidade de configurar vários aspectos da segurança do cluster Kubernetes e dos aplicativos em execução nele. Gostei do exame, ele analisa a segurança de vários pontos de vista e também usa ferramentas externas muito úteis, como Falco, Trivy, kube-bench, Open Policy Agent, gVisor, etc. O exame em si me pareceu moderadamente difícil, ao contrário CKA, que é mais voltado para iniciantes no Kubernetes.
Primeiro falarei sobre o exame e a preparação para ele em geral e, em seguida, passarei aos tópicos abordados no exame.
No momento, existem apenas dois exames de segurança do Kubernetes - este é, na verdade, o próprio CKS, assim como o Red Hat Certified Specialist em Segurança: Containers e OpenShift , lidando com segurança OpenShift. Esses dois exames se sobrepõem de várias maneiras, no entanto, de acordo com a Openshift, acho que o exame é ainda mais difícil (fui reprovado).
O exame custa $ 300 separadamente , o curso oficial Kubernetes Security Fundamentals (LFS260) custa $ 299 , você pode comprar o curso e o exame juntos por $ 499 . Comprei o curso e o exame juntos por $ 200 na tradicional Venda de Ano Novo da Linux Foundation.
CKS CKA (Certified Kubernetes Administrator). CKS, , CKA. , CKS CKA.
. :
Linux Foundation: Kubernetes Security Fundamentals (LFS260). Linux Foundation, . , , , , - PDF ( , ?!), . , . , .
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15-20 , 2 .. 6-8 . . , Kubernetes killer.sh, 1 40 .
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- . CKS. :
Cluster Setup (10%)
Use Network security policies to restrict cluster level access
Use CIS benchmark to review the security configuration of Kubernetes components (etcd, kubelet, kubedns, kubeapi)
Properly set up Ingress objects with security control
Protect node metadata and endpoints
Minimize use of, and access to, GUI elements
Verify platform binaries before deploying
Cluster Hardening (15%)
Restrict access to Kubernetes API
Use Role Based Access Controls to minimize exposure
Exercise caution in using service accounts e.g. disable defaults, minimize permissions on newly created ones
Update Kubernetes frequently
System Hardening15%
Minimize host OS footprint (reduce attack surface)
Minimize IAM roles
Minimize external access to the network
Appropriately use kernel hardening tools such as AppArmor, seccomp
Minimize Microservice Vulnerabilities (20%)
Setup appropriate OS level security domains e.g. using PSP, OPA, security contexts
Manage Kubernetes secrets
Use container runtime sandboxes in multi-tenant environments (e.g. gvisor, kata containers)
Implement pod to pod encryption by use of mTLS
Supply Chain Security20%
Minimize base image footprint
Secure your supply chain: whitelist allowed registries, sign and validate images
Use static analysis of user workloads (e.g.Kubernetes resources, Docker files)
Scan images for known vulnerabilities
Monitoring, Logging and Runtime Security20%
Perform behavioral analytics of syscall process and file activities at the host and container level to detect malicious activities
Detect threats within physical infrastructure, apps, networks, data, users and workloads
Detect all phases of attack regardless where it occurs and how it spreads
Perform deep analytical investigation and identification of bad actors within environment
Ensure immutability of containers at runtime
Use Audit Logs to monitor access
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hostPath
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hostNetwork
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kube-system
ClusterRoleBinding
cluster-admin
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Kubernetes, RBAC , Open Policy Agent (OPA). Kubernetes , Rego. Kubernetes validating admission webhook OPA Gatekeeper. Custom Resource Definition. , costcenter.
apiVersion: templates.gatekeeper.sh/v1beta1
kind: ConstraintTemplate
metadata:
name: k8srequiredlabels
spec:
crd:
spec:
names:
kind: K8sRequiredLabels
validation:
openAPIV3Schema:
properties:
labels:
type: array
items: string
targets:
- target: admission.k8s.gatekeeper.sh
rego: |
package k8srequiredlabels
violation[{"msg": msg, "details": {"missing_labels": missing}}] {
provided := {label | input.review.object.metadata.labels[label]}
required := {label | label := input.parameters.labels[_]}
missing := required - provided
count(missing) > 0
msg := sprintf("you must provide labels: %v", [missing])
}
---
apiVersion: constraints.gatekeeper.sh/v1beta1
kind: K8sRequiredLabels
metadata:
name: ns-must-have-costcenter
spec:
match:
kinds:
- apiGroups: [""]
kinds: ["Namespace"]
parameters:
labels: ["costcenter"]
costcenter :
Error from server (you must provide labels: "costcenter"): error when creating "ns.yaml": admission webhook "validating-webhook.openpolicyagent.org" denied the request: you must provide labels: "costcenter"
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defaultAllowPrivilegeEscalation
defaultAddCapabilities
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(, Chrome, Vivaldi). :
, . https://kubernetes.io/docs.
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