【Azure Bastion】Azure Bastion的Azure安全基线

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

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.

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

For more information, see the Microsoft cloud security benchmark: Network security.

Description: Service supports deployment into customer's private Virtual Network (VNet). Learn more.

Configuration Guidance: Deploy the Azure Bastion into a virtual network with the subnet at least /26 or larger.

Reference: Tutorial: Deploy Bastion

Description: Service network traffic respects Network Security Groups rule assignment on its subnets. Learn more.

Configuration Guidance: Use network security groups (NSG) to restrict or monitor traffic by port, protocol, source IP address, or destination IP address. Create NSG rules to restrict your service's open ports (such as preventing management ports from being accessed from untrusted networks).

Reference: Working with NSG access and Azure Bastion

Azure Policy built-in definitions - Microsoft.Network:

Description: Service native IP filtering capability for filtering network traffic (not to be confused with NSG or Azure Firewall). Learn more.

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

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.

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

For more information, see the Microsoft cloud security benchmark: Identity management.

Description: Service supports using Azure AD authentication for data plane access. Learn more.

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

Description: Local authentications methods supported for data plane access, such as a local username and password. Learn more.

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

Description: Data plane actions support authentication using managed identities. Learn more.

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

Description: Data plane supports native use of Azure Key Vault for credential and secrets store. Learn more.

Configuration Guidance: You can store your SSH keys as Azure Key Vault secrets and use these secrets to connect to your virtual machines using Azure Bastion. You can control user access to these secrets by assigning Key Vault access policies either on individual users or Azure AD groups.

For more information, see the Microsoft cloud security benchmark: Privileged access.

Description: Service has the concept of a local administrative account. Learn more.

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

Description: Azure Role-Based Access Control (Azure RBAC) can be used to managed access to service's data plane actions. Learn more.

Feature notes: Azure Bastion itself does not support Azure RBAC for users access.

However, when connecting to virtual machines using Azure Bastion your user will need the following role assignments:

• Reader role on the target virtual machine
• Reader role on the NIC with the private IP of the target virtual machine
• Reader role on the Azure Bastion resource

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

Description: Customer Lockbox can be used for Microsoft support access. Learn more.

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

For more information, see the Microsoft cloud security benchmark: Data protection.

Description: Service supports data in-transit encryption for data plane. Learn more.

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

Description: Data at-rest encryption using platform keys is supported, any customer content at rest is encrypted with these Microsoft managed keys. Learn more.

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

Description: The service supports Azure Key Vault integration for any customer keys, secrets, or certificates. Learn more.

Configuration Guidance: You can store and manage your SSH keys in Azure Key Vault secrets and use these secrets to connect to your virtual machines using Azure Bastion.

Reference: Connect: Using a private key stored in Azure Key Vault

For more information, see the Microsoft cloud security benchmark: Asset management.

Description: Service configurations can be monitored and enforced via Azure Policy. Learn more.

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.

For more information, see the Microsoft cloud security benchmark: Logging and threat detection.

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.

Configuration Guidance: Enable resource logs for the Azure Bastion. As users connect to workloads using Azure Bastion, Bastion can log diagnostics of the remote sessions. You can then use the diagnostics to view which users connected to which workloads, at what time, from where, and other such relevant logging information.

Reference: Azure Bastion Resource Logs

For more information, see the Microsoft cloud security benchmark: Backup and recovery.

Description: The service can be backed up by the Azure Backup service. Learn more.

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

Description: Service supports its own native backup capability (if not using Azure Backup). Learn more.

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

• See the Microsoft cloud security benchmark overview
• Learn more about Azure security baselines