Azure security baseline for Azure Kubernetes Service (AKS)
This security baseline applies guidance from the Microsoft cloud security benchmark version 1.0 to Azure Kubernetes Service (AKS). The Microsoft cloud security benchmark provides recommendations on how you can secure your cloud solutions on Azure. The content is grouped by the security controls defined by the Microsoft cloud security benchmark and the related guidance applicable to Azure Kubernetes Service (AKS).
You can monitor this security baseline and its recommendations using Microsoft Defender for Cloud. Azure Policy definitions will be listed in the Regulatory Compliance section of the Microsoft Defender for Cloud portal page.
When a feature has relevant Azure Policy Definitions, they are listed in this baseline to help you measure compliance with the Microsoft cloud security benchmark controls and recommendations. Some recommendations may require a paid Microsoft Defender plan to enable certain security scenarios.
Note
Features not applicable to Azure Kubernetes Service (AKS) have been excluded. To see how Azure Kubernetes Service (AKS) completely maps to the Microsoft cloud security benchmark, see the full Azure Kubernetes Service (AKS) security baseline mapping file.
Security profile
The security profile summarizes high-impact behaviors of Azure Kubernetes Service (AKS), which may result in increased security considerations.
| Service Behavior Attribute | Value |
|---|---|
| Product Category | Containers |
| Customer can access HOST / OS | No Access |
| Service can be deployed into customer's virtual network | True |
| Stores customer content at rest | True |
Network security
For more information, see the Microsoft cloud security benchmark: Network security.
NS-1: Establish network segmentation boundaries
Features
Virtual Network Integration
Description: Service supports deployment into customer's private Virtual Network (VNet). Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | True | Microsoft |
Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.
Reference: Use kubenet networking with your own IP address ranges in Azure Kubernetes Service (AKS)
Network Security Group Support
Description: Service network traffic respects Network Security Groups rule assignment on its subnets. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | True | Microsoft |
Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.
Reference: Network security groups
NS-2: Secure cloud services with network controls
Features
Azure Private Link
Description: Service native IP filtering capability for filtering network traffic (not to be confused with NSG or Azure Firewall). Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Deploy private endpoints for all Azure resources that support the Private Link feature, to establish a private access point for the resources.
Reference: Create a private Azure Kubernetes Service cluster
Disable Public Network Access
Description: Service supports disabling public network access either through using service-level IP ACL filtering rule (not NSG or Azure Firewall) or using a 'Disable Public Network Access' toggle switch. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Use the Azure CLI to disable the Public FQDN on a private Azure Kubernetes Service cluster.
Reference: Create a private Azure Kubernetes Service cluster
Microsoft Defender for Cloud monitoring
Azure Policy built-in definitions - Microsoft.ContainerService:
| Name (Azure portal) |
Description | Effect(s) | Version (GitHub) |
|---|---|---|---|
| Authorized IP ranges should be defined on Kubernetes Services | Restrict access to the Kubernetes Service Management API by granting API access only to IP addresses in specific ranges. It is recommended to limit access to authorized IP ranges to ensure that only applications from allowed networks can access the cluster. | Audit, Disabled | 2.0.1 |
Identity management
For more information, see the Microsoft cloud security benchmark: Identity management.
IM-1: Use centralized identity and authentication system
Features
Azure AD Authentication Required for Data Plane Access
Description: Service supports using Azure AD authentication for data plane access. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Use Azure Active Directory (Azure AD) as the default authentication method to control your data plane access.
Reference: AKS-managed Azure Active Directory Integration
Local Authentication Methods for Data Plane Access
Description: Local authentications methods supported for data plane access, such as a local username and password. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Feature notes: Avoid the usage of local authentication methods or accounts, these should be disabled wherever possible. Instead use Azure AD to authenticate where possible.
Configuration Guidance: You can authenticate, authorize, secure, and control access to Kubernetes clusters using Kubernetes role-based access control (Kubernetes RBAC) or by using Azure Active Directory and Azure RBAC.
Reference: Access and identity options for Azure Kubernetes Service (AKS)
IM-3: Manage application identities securely and automatically
Features
Managed Identities
Description: Data plane actions support authentication using managed identities. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | True | Microsoft |
Feature notes: By default, when you create an AKS cluster a system-assigned managed identity is automatically created. If you are not using the Azure CLI for deployment but using your own VNet, attached Azure disk, static IP address, route table or user-assigned kubelet identity that are outside of the worker node resource group, it's recommended to use user-assigned control plane identity.
Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.
Reference: Use a managed identity in Azure Kubernetes Service
Service Principals
Description: Data plane supports authentication using service principals. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: There is no current Microsoft guidance for this feature configuration. Please review and determine if your organization wants to configure this security feature.
Reference: Create a Service Principal
IM-7: Restrict resource access based on conditions
Features
Conditional Access for Data Plane
Description: Data plane access can be controlled using Azure AD Conditional Access Policies. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Define the applicable conditions and criteria for Azure Active Directory (Azure AD) conditional access in the workload. Consider common use cases such as blocking or granting access from specific locations, blocking risky sign-in behavior, or requiring organization-managed devices for specific applications.
Reference:
- IM-1: Use centralized identity and authentication system
- Use Conditional Access with Azure AD and AKS
IM-8: Restrict the exposure of credential and secrets
Features
Service Credential and Secrets Support Integration and Storage in Azure Key Vault
Description: Data plane supports native use of Azure Key Vault for credential and secrets store. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Ensure that secrets and credentials are stored in secure locations such as Azure Key Vault, instead of embedding them into code or configuration files.
Reference: CSI Secret Store
Privileged access
For more information, see the Microsoft cloud security benchmark: Privileged access.
PA-1: Separate and limit highly privileged/administrative users
Features
Local Admin Accounts
Description: Service has the concept of a local administrative account. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Feature notes: Avoid the usage of local authentication methods or accounts, these should be disabled wherever possible. Instead use Azure AD to authenticate where possible.
Configuration Guidance: You can authenticate, authorize, secure, and control access to Kubernetes clusters using Kubernetes role-based access control (Kubernetes RBAC) or by using Azure Active Directory and Azure RBAC.
If not required for routine administrative operations, disable or restrict any local admin accounts for only emergency use.
Reference: Access and identity options for Azure Kubernetes Service (AKS)
PA-7: Follow just enough administration (least privilege) principle
Features
Azure RBAC for Data Plane
Description: Azure Role-Based Access Control (Azure RBAC) can be used to managed access to service's data plane actions. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Use Azure role-based access control (Azure RBAC) to manage Azure resource access through built-in role assignments. Azure RBAC roles can be assigned to users, groups, service principals, and managed identities.
Reference: Use Azure RBAC for Kubernetes Authorization
Microsoft Defender for Cloud monitoring
Azure Policy built-in definitions - Microsoft.ContainerService:
| Name (Azure portal) |
Description | Effect(s) | Version (GitHub) |
|---|---|---|---|
| Azure Role-Based Access Control (RBAC) should be used on Kubernetes Services | To provide granular filtering on the actions that users can perform, use Azure Role-Based Access Control (RBAC) to manage permissions in Kubernetes Service Clusters and configure relevant authorization policies. | Audit, Disabled | 1.0.3 |
PA-8: Determine access process for cloud provider support
Features
Customer Lockbox
Description: Customer Lockbox can be used for Microsoft support access. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: In support scenarios where Microsoft needs to access your data, use Customer Lockbox to review, then approve or reject each of Microsoft's data access requests.
Reference: Customer Lockbox for Microsoft Azure
Data protection
For more information, see the Microsoft cloud security benchmark: Data protection.
DP-1: Discover, classify, and label sensitive data
Features
Sensitive Data Discovery and Classification
Description: Tools (such as Azure Purview or Azure Information Protection) can be used for data discovery and classification in the service. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| False | Not Applicable | Not Applicable |
Configuration Guidance: This feature is not supported to secure this service.
DP-2: Monitor anomalies and threats targeting sensitive data
Features
Data Leakage/Loss Prevention
Description: Service supports DLP solution to monitor sensitive data movement (in customer's content). Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: If required for compliance of data loss prevention (DLP), you can use a host based DLP solution from Azure Marketplace or a Microsoft 365 DLP solution to enforce detective and/or preventative controls to prevent data exfiltration.
Reference: Enable Microsoft Defender for Containers
DP-3: Encrypt sensitive data in transit
Features
Data in Transit Encryption
Description: Service supports data in-transit encryption for data plane. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Enable secure transfer in services where there is a native data in transit encryption feature built in. Enforce HTTPS on any web applications and services and ensure TLS v1.2 or later is used. Legacy versions such as SSL 3.0, TLS v1.0 should be disabled. For remote management of Virtual Machines, use SSH (for Linux) or RDP/TLS (for Windows) instead of an unencrypted protocol.
Reference: Use TLS with an ingress controller on Azure Kubernetes Service (AKS)
Microsoft Defender for Cloud monitoring
Azure Policy built-in definitions - Microsoft.ContainerService:
| Name (Azure portal) |
Description | Effect(s) | Version (GitHub) |
|---|---|---|---|
| Kubernetes clusters should be accessible only over HTTPS | Use of HTTPS ensures authentication and protects data in transit from network layer eavesdropping attacks. This capability is currently generally available for Kubernetes Service (AKS), and in preview for Azure Arc enabled Kubernetes. For more info, visit https://aka.ms/kubepolicydoc | audit, Audit, deny, Deny, disabled, Disabled | 8.1.0 |
DP-4: Enable data at rest encryption by default
Features
Data at Rest Encryption Using Platform Keys
Description: Data at-rest encryption using platform keys is supported, any customer content at rest is encrypted with these Microsoft managed keys. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Feature notes: Host-based encryption is different than server-side encryption (SSE), which is used by Azure Storage. Azure-managed disks use Azure Storage to automatically encrypt data at rest when saving data. Host-based encryption uses the host of the VM to handle encryption before the data flows through Azure Storage.
Configuration Guidance: Enable data at rest encryption using platform managed (Microsoft managed) keys where not automatically configured by the service.
Reference: Host-based encryption on Azure Kubernetes Service (AKS)
DP-5: Use customer-managed key option in data at rest encryption when required
Features
Data at Rest Encryption Using CMK
Description: Data at-rest encryption using customer-managed keys is supported for customer content stored by the service. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: If required for regulatory compliance, define the use case and service scope where encryption using customer-managed keys are needed. Enable and implement data at rest encryption using customer-managed key for those services.
Reference: Host-based encryption on Azure Kubernetes Service (AKS)
DP-6: Use a secure key management process
Features
Key Management in Azure Key Vault
Description: The service supports Azure Key Vault integration for any customer keys, secrets, or certificates. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Use Azure Key Vault to create and control the life cycle of your encryption keys, including key generation, distribution, and storage. Rotate and revoke your keys in Azure Key Vault and your service based on a defined schedule or when there is a key retirement or compromise. When there is a need to use customer-managed key (CMK) in the workload, service, or application level, ensure you follow the best practices for key management: Use a key hierarchy to generate a separate data encryption key (DEK) with your key encryption key (KEK) in your key vault. Ensure keys are registered with Azure Key Vault and referenced via key IDs from the service or application. If you need to bring your own key (BYOK) to the service (such as importing HSM-protected keys from your on-premises HSMs into Azure Key Vault), follow recommended guidelines to perform initial key generation and key transfer.
Reference: Host-based encryption on Azure Kubernetes Service (AKS)
DP-7: Use a secure certificate management process
Features
Certificate Management in Azure Key Vault
Description: The service supports Azure Key Vault integration for any customer certificates. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Use Azure Key Vault to create and control the certificate lifecycle, including creation, importing, rotation, revocation, storage, and purging of the certificate. Ensure the certificate generation follows defined standards without using any insecure properties, such as: insufficient key size, overly long validity period, insecure cryptography. Setup automatic rotation of the certificate in Azure Key Vault and the Azure service (if supported) based on a defined schedule or when there is a certificate expiration. If automatic rotation is not supported in the application, ensure they are still rotated using manual methods in Azure Key Vault and the application.
Reference: Use TLS with your own certificates with Secrets Store CSI Driver
Asset management
For more information, see the Microsoft cloud security benchmark: Asset management.
AM-2: Use only approved services
Features
Azure Policy Support
Description: Service configurations can be monitored and enforced via Azure Policy. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Use Microsoft Defender for Cloud to configure Azure Policy to audit and enforce configurations of your Azure resources. Use Azure Monitor to create alerts when there is a configuration deviation detected on the resources. Use Azure Policy [deny] and [deploy if not exists] effects to enforce secure configuration across Azure resources.
Reference: AKS Built-in Azure Policy
Logging and threat detection
For more information, see the Microsoft cloud security benchmark: Logging and threat detection.
LT-1: Enable threat detection capabilities
Features
Microsoft Defender for Service / Product Offering
Description: Service has an offering-specific Microsoft Defender solution to monitor and alert on security issues. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Microsoft Defender for Containers is the cloud-native solution that is used to secure your containers so you can improve, monitor, and maintain the security of your clusters, containers, and their applications.
Reference: Enable Microsoft Defender for Containers
Microsoft Defender for Cloud monitoring
Azure Policy built-in definitions - Microsoft.ContainerService:
| Name (Azure portal) |
Description | Effect(s) | Version (GitHub) |
|---|---|---|---|
| Azure Kubernetes Service clusters should have Defender profile enabled | Microsoft Defender for Containers provides cloud-native Kubernetes security capabilities including environment hardening, workload protection, and run-time protection. When you enable the SecurityProfile.AzureDefender on your Azure Kubernetes Service cluster, an agent is deployed to your cluster to collect security event data. Learn more about Microsoft Defender for Containers in https://docs.microsoft.com/azure/defender-for-cloud/defender-for-containers-introduction?tabs=defender-for-container-arch-aks | Audit, Disabled | 2.0.1 |
LT-4: Enable logging for security investigation
Features
Azure Resource Logs
Description: Service produces resource logs that can provide enhanced service-specific metrics and logging. The customer can configure these resource logs and send them to their own data sink like a storage account or log analytics workspace. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Enable resource logs for the service. For example, Key Vault supports additional resource logs for actions that get a secret from a key vault or and Azure SQL has resource logs that track requests to a database. The content of resource logs varies by the Azure service and resource type.
Reference: Collect resource logs
Posture and vulnerability management
For more information, see the Microsoft cloud security benchmark: Posture and vulnerability management.
PV-3: Establish secure configurations for compute resources
Features
Custom Container Images
Desription: Service supports using user-supplied container images or pre-built images from the marketplace with certain baseline configurations pre-applied. Learn more
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: When using Azure Container Registry (ACR) with Azure Kubernetes Service (AKS), you need to establish an authentication mechanism. Configuring the required permissions between ACR and AKS can be accomplished using the Azure CLI, Azure PowerShell, and Azure portal. The AKS to ACR integration assigns the AcrPull role to the Azure Active Directory (Azure AD) managed identity associated with the agent pool in your AKS cluster.
Reference: Integrate Azure Container Registry with Azure Kubernetes Service - Azure Kubernetes Service
PV-5: Perform vulnerability assessments
Features
Vulnerability Assessment using Microsoft Defender
Desription: Service can be scanned for vulnerability scan using Microsoft Defender for Cloud or other Microsoft Defender services embedded vulnerability assessment capability (including Microsoft Defender for server, container registry, App Service, SQL, and DNS). Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: By default, when enabling the plan through the Azure portal, Microsoft Defender for Containers is configured to automatically install required components to provide the protections offered by plan, including the assignment of a default workspace.
Reference: Vulnerability management for Azure Kubernetes Service - Azure Kubernetes Service
Backup and recovery
For more information, see the Microsoft cloud security benchmark: Backup and recovery.
BR-1: Ensure regular automated backups
Features
Azure Backup
Description: The service can be backed up by the Azure Backup service. Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| True | False | Customer |
Configuration Guidance: Enable Azure Backup and configure the backup source (such as Azure Virtual Machines, SQL Server, HANA databases, or File Shares) on a desired frequency and with a desired retention period. For Azure Virtual Machines, you can use Azure Policy to enable automatic backups.
Reference: Back up Azure Kubernetes Service using Azure Backup
Service Native Backup Capability
Description: Service supports its own native backup capability (if not using Azure Backup). Learn more.
| Supported | Enabled By Default | Configuration Responsibility |
|---|---|---|
| False | Not Applicable | Not Applicable |
Configuration Guidance: This feature is not supported to secure this service.
Next steps
- See the Microsoft cloud security benchmark overview
- Learn more about Azure security baselines