Ensure that default service accounts are not actively used.

高レベル 1自動eks

説明

Default service accounts in EKS should not be used as the active identity for ordinary application or automation workloads. If a Pod does not specify a service account, Kubernetes automatically assigns the namespace default service account, and that account can authenticate to the Kubernetes API through its mounted token. Requires kubectl with cluster-wide read access (KUBECONFIG); system namespaces are excluded and listed resources must be remediated or documented as exceptions. Fails when a default service account does not set automountServiceAccountToken: false or is bound to a Role/ClusterRole.

チェック方法

監査方法: シェルコマンド

shell

sa=$(kubectl get serviceaccounts -A -o go-template='{{range .items}}{{if eq .metadata.name "default"}}{{.metadata.namespace}} {{.automountServiceAccountToken}}{{"\n"}}{{end}}{{end}}') || exit 1
rb=$(kubectl get rolebindings,clusterrolebindings -A -o go-template='{{range .items}}{{$b:=.metadata.name}}{{$bn:=.metadata.namespace}}{{range .subjects}}{{if eq .kind "ServiceAccount"}}{{if eq .name "default"}}{{if .namespace}}{{.namespace}}{{else}}{{$bn}}{{end}} {{$b}}{{"\n"}}{{end}}{{end}}{{end}}{{end}}') || exit 1
bad=$(printf '%s\n' "$sa" | awk -v ex='^(kube-system|kube-public|kube-node-lease)$' 'NF && $1 !~ ex && $2!="false" {print "automount: " $1}')
bad2=$(printf '%s\n' "$rb" | awk -v ex='^(kube-system|kube-public|kube-node-lease)$' 'NF && $1 !~ ex {print "binding: " $0}')
if [ -z "$bad$bad2" ]; then echo compliant; else printf '%s\n%s\n' "$bad" "$bad2" | grep . | head -n 25; fi

期待される出力: compliant

修正方法

修正方法: ガイダンスまたは IaC パッチ

Create dedicated service accounts for workloads that need Kubernetes API access, IRSA, or EKS Pod Identity, and update those workloads to explicitly set serviceAccountNam rather than relying on the namespace default service account. For workloads that do not need Kubernetes API access, disable service account token auto-mounting and avoid using the default service account as the active workload identity. Also review the default service account in each namespace and ensure it is not bound to unnecessary RBAC permissions.

プロパティ

オペレーティングシステム: すべて
タグ: ekspoliciesrbac
参照: CIS Amazon Elastic Kubernetes Service (EKS) Benchmark v2.0.0 - 4.1.5 Ensure that default service accounts are not actively used.

このホストをチェック

監査が許可されているマシンで実行してください。スキャンは読み取り専用です。

shell

tmaegis scan --target eks