cis-aks-v180-4-1-2

name	cis-aks-v180-4.1.2
description	Minimize access to secrets (Manual)
category	cis-aks
version	1.8.0
author	cyberstrike-official
tags	["cis","aks","kubernetes","azure","rbac","service-accounts","secrets","access-control"]
cis_id	4.1.2
cis_benchmark	CIS Azure Kubernetes Service (AKS) Benchmark v1.8.0
tech_stack	["kubernetes","azure","aks"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

4.1.2 Minimize access to secrets (Manual)

Profile Applicability

• Level 1

Description

The Kubernetes API stores secrets, which may be service account tokens for the Kubernetes API or credentials used by workloads in the cluster. Access to these secrets should be restricted to the smallest possible group of users to reduce the risk of privilege escalation.

Rationale

Inappropriate access to secrets stored within the Kubernetes cluster can allow for an attacker to gain additional access to the Kubernetes cluster or external resources whose credentials are stored as secrets.

Impact

Care should be taken not to remove access to secrets to system components which require this for their operation.

Audit

Review the users who have get, list or watch access to secrets objects in the Kubernetes API.

Remediation

Where possible, remove get, list and watch access to secret objects in the cluster.

Default Value

By default, the following list of principals have get privileges on secret objects:

CLUSTERROLEBINDING	SUBJECT
cluster-admin (Group)	system:masters
system:controller:clusterrole-aggregation-controller (ServiceAccount kube-system)	clusterrole-aggregation-controller
system:controller:expand-controller (ServiceAccount kube-system)	expand-controller
system:controller:generic-garbage-collector (ServiceAccount kube-system)	generic-garbage-collector
system:controller:namespace-controller (ServiceAccount kube-system)	namespace-controller
system:controller:persistent-volume-binder (ServiceAccount kube-system)	persistent-volume-binder
system:kube-controller-manager (User)	system:kube-controller-manager

References

1. https://docs.microsoft.com/security/benchmark/azure/security-controls-v2-identity-management#im-7-eliminate-unintended-credential-exposure