Azure Kubernetes Service (AKS)
TMA-AKS-4.1.6
Ensure that Service Account Tokens are only mounted where necessary
Description
Review that service account tokens in AKS are mounted only for pods that require Kubernetes API access or an explicitly configured workload identity flow. Confirm that pods and service accounts are not broadly relying on default token mounting, and that token projection is limited to workloads with a defined operational need. Requires kubectl with cluster-wide read access (KUBECONFIG); system namespaces are excluded and listed resources must be remediated or documented as exceptions. Reports pods with an auto-mounted service account token (kube-api-access-* volume).
How it is checked
Audit method: Shell command
out=$(kubectl get pods -A -o go-template='{{range .items}}{{.metadata.namespace}} {{.metadata.name}}{{range .spec.volumes}} {{.name}}{{end}}{{"\n"}}{{end}}') || exit 1
bad=$(printf '%s\n' "$out" | awk -v ex='^(kube-system|kube-public|kube-node-lease|gatekeeper-system|azure-arc)$' 'NF && $1 !~ ex && ($0 ~ / kube-api-access-/)')
if [ -z "$bad" ]; then echo compliant; else printf '%s\n' "$bad" | head -n 25; fi- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
Apply the following steps to reduce unnecessary service account token mounting in AKS: • Set automountServiceAccountToken to false for pods and service accounts that do not require Kubernetes API access. AKS policy guidance states that this increases security by avoiding default token auto-mounting. • Update workloads to use a dedicated serviceAccountName only where a service account token is operationally required, instead of inheriting token behavior from the namespace default service account. AKS states that service account credentials are used by authorized pods to communicate with the API server. • For workloads that need Azure resource access, use Microsoft Entra Workload ID with explicit workload configuration rather than broad default token mounting. AKS documents that workload identity token projection is enabled only for explicitly configured pods.
Properties
- Operating systems
- Any
- Tags
- akspoliciesrbac
- Reference
- CIS Azure Kubernetes Service (AKS) Benchmark v2.0.0 - 4.1.6 Ensure that Service Account Tokens are only mounted where necessary
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target aks