Azure security baseline for Azure Data Explorer

This security baseline applies guidance from the Microsoft cloud security benchmark version 1.0 to Azure Data Explorer. 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 Data Explorer.

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.

Security profile

The security profile summarizes high-impact behaviors of Azure Data Explorer, which may result in increased security considerations.

Service Behavior Attribute	Value
Product Category	Analytics, Databases
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	False	Customer

Feature notes: We highly recommended using private endpoints to secure network access to your cluster. This option has many advantages over virtual network injection that results in lower maintenance overhead, including a simpler deployment process and being more robust to virtual network changes.

Configuration Guidance: Deploy Azure Data Explorer cluster into a subnet in your Virtual Network (VNet). This will allow you to implement NSG rules to restrict on your Azure Data Explorer cluster traffic and connect your on-premises network to Azure Data Explorer cluster's subnet.

Reference: Deploy Azure Data Explorer cluster into your Virtual Network

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	False	Customer

Feature notes: It is supported and required to configure Network Security Group rules in case Azure Data Explorer was injected into the customer virtual network. It is not recommended to inject Azure Data Explorer into a virtual network. It is recommended to follow a Private Endpoint based network security implementation: Private endpoints for Azure Data Explorer.

Configuration Guidance: In case you decide to inject Azure Data Explorer into a virtual network (a private endpoint-based solution is highly recommended) we require you to use subnet delegation for your cluster's deployment. To do so, you must delegate the subnet to Microsoft.Kusto/clusters before creating the cluster in the subnet.

By enabling subnet delegation on the cluster's subnet, you enable the service to define its pre-conditions for deployment in the form of Network Intent Policies. When creating the cluster in the subnet, the NSG configurations mentioned in the following sections are automatically created for you.

Reference: Configure Network Security Group rules

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: It is highly recommended to use private endpoints to secure network access to your cluster. This option has many advantages over virtual network integration that results in lower maintenance overhead, including a simpler deployment process and being more robust to virtual network changes.

Reference: Private endpoints for Azure Data Explorer

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: Disable public network access either using the service-level IP ACL filtering rule or a toggling switch for public network access.

Reference: Restrict public access to your Azure Data Explorer cluster

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: How to authenticate with Azure Active Directory (Azure AD) for Azure Data Explorer access

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
False	Not Applicable	Not Applicable

Configuration Guidance: This feature is not supported to secure this service.

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: Azure Data Explorer allows authentication on its data plane with any Azure Active Directory identity. This means System and User Managed Identities are supported. Moreover, Azure Data Explorer supports use of Managed Identities to authenticate on other services for Ingestion and Query. For more information, please visit: Managed identities overview.

Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.

Reference: Azure Active Directory authentication

Service Principals

Description: Data plane supports authentication using service principals. Learn more.

Supported	Enabled By Default	Configuration Responsibility
True	True	Microsoft

Feature notes: Azure Data Explorer supports all Azure Active Directory identity types, including service principals

Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.

Reference: Azure Active Directory authentication using an application

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: Conditional Access with Azure Data Explorer

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
False	Not Applicable	Not Applicable

Configuration Guidance: This feature is not supported to secure this service.

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
False	Not Applicable	Not Applicable

Configuration Guidance: This feature is not supported to secure this service.

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
False	Not Applicable	Not Applicable

Feature notes: Azure Data Explorer enables you to control access to the data plane (databases and tables), using a role-based access control model. Under this model, principals (users, groups, and apps) are mapped to roles. Principals can access resources according to the roles they're assigned. However the Azure Data Explorer data plane is decoupled from the Azure RBAC for the control plane.

Refer to: Manage Azure Data Explorer database permissions

Configuration Guidance: This feature is not supported to secure this service.

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	True	Microsoft

Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.

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
True	False	Customer

Feature notes: Azure Data Explorer is supported in Microsoft Purview.

Configuration Guidance: Azure Data Explorer is supported in Microsoft Purview. You can use Azure Purview to scan, classify, and label any sensitive data that resides in Azure Data Explorer.

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: Restricting outbound access of your cluster is important to mitigate risks like data exfiltration. A malicious actor could potentially create an external table to a storage account and extract large amounts of data. You can control outbound access at the cluster level by defining callout policies. Managing callout policies enables you to allow outbound access to specified SQL, storage, or other endpoints.

Reference: Restrict outbound access from your Azure Data Explorer cluster

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	True	Microsoft

Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.

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	True	Microsoft

Configuration Guidance: No additional configurations are required as this is enabled on a default deployment.

Reference: Data Encryption in Azure Data Explorer

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: For additional control over encryption keys, you can supply customer-managed keys to use for data encryption. You can manage encryption of your data at the storage level with your own keys. A customer-managed key is used to protect and control access to the root encryption key, which is used to encrypt and decrypt all data. Customer-managed keys offer greater flexibility to create, rotate, disable, and revoke access controls. You can also audit the encryption keys used to protect your data.

Reference: Encryption using configure customer-managed keys

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
False	Not Applicable	Not Applicable

Configuration Guidance: This feature is not supported to secure this service.

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: Azure Policy Regulatory Compliance controls for Azure Data Explorer

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
False	Not Applicable	Not Applicable

Configuration Guidance: This feature is not supported to secure this service.

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: Azure Data Explorer uses diagnostic logs for insights on ingestion, commands, query, and tables. You can export operation logs to Azure Storage, event hub, or Log Analytics to monitor ingestion, commands, and query status. Logs from Azure Storage and Azure Event Hubs can be routed to a table in your Azure Data Explorer cluster for further analysis.

Reference: Monitor Azure Data Explorer ingestion, commands, queries, and tables using diagnostic logs

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
False	Not Applicable	Not Applicable

Configuration Guidance: This feature is not supported to secure this service.

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