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Azure AI Foundry Network Access Restriction

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Risk Level: Medium (should be achieved)

To ensure that only allowed networks can access the Azure AI Foundry resources deployed across your organization, enable the "Azure AI Services resources should restrict network access" policy assignment within your Microsoft Azure cloud account. This action enforces security and compliance standards for AI resources throughout your organization.

Security
Cost
optimisation

Microsoft Azure Policy is a powerful service for enforcing organizational standards and assessing cloud compliance at scale. It allows you to define, assign, and manage policies that enforce rules and effects over your cloud resources. This helps ensure consistent security configurations, prevents misconfigurations, and maintains compliance with corporate standards and service level agreements (SLAs). A policy assignment is a policy definition or initiative that's applied to a specific scope, such as a subscription or a resource group. This is especially useful in enterprise environments where multiple teams deploy services and consistent security standards must be maintained across all deployments. By enforcing the "Azure AI Services resources should restrict network access" policy, you can minimize the attack surface by preventing unauthorized access from public networks, thus protecting sensitive data and AI models from external threats and reducing the risk of data exfiltration. This restriction enforces a secure network boundary for your AI Foundry resources.

Audit

To determine if the "Azure AI Services resources should restrict network access" policy is assigned to your Azure cloud subscriptions, perform the following operations:

Using Azure Console

01 Sign in to the Microsoft Azure Portal.

02 Navigate to Azure Policy blade available at https://portal.azure.com/#blade/Microsoft_Azure_Policy/PolicyMenuBlade.

03 In the left navigation panel, under Authoring, choose Assignments to access the list with all the initiative and policy assignments available within your Azure account.

04 On the Assignments page, perform the following actions:

  1. For Scope, select the Azure subscription that you want to examine.
  2. For Definition type, choose Policy to display only the policy assignments created for the selected subscription.
  3. Click inside the Search box, enter Azure AI Services resources should restrict network access, and press Enter to search for the specific policy assignment. If no results are returned, instead the following message is displayed: No policies found in the given scope, the selected policy assignment is not implemented within the selected Azure subscription.
  4. Repeat steps no. 1 – 3 for each subscription available in your Microsoft Azure cloud account.

Using Azure CLI

01 Run account list command (Windows/macOS/Linux) with custom output filters to list the IDs of the cloud subscriptions available in your Azure cloud account: 

az account list
	--query '[*].id'

02 The command output should return the requested subscription identifiers (IDs): 

[
	"abcdabcd-1234-abcd-1234-abcdabcdabcd",
	"abcd1234-abcd-1234-abcd-abcd1234abcd"
]

03 Run policy assignment list command (Windows/macOS/Linux) with the ID of the Azure subscription that you want to examine as the identifier parameter and custom output filters to list the name and the policy definition ID of each Azure policy assignment, available in the selected subscription: 

az policy assignment list
	--scope /subscriptions/abcdabcd-1234-abcd-1234-abcdabcdabcd
	--output table
	--query '[*].{"name": displayName,"policyDefinitionId": policyDefinitionId}'

04 The command output should return the requested policy information: 

Name                                                                                     PolicyDefinitionId
---------------------------------------------------------------------------------------  -----------------------------------------------------------
Linux virtual machines should have Azure Monitor Agent installed                         /.../policyDefinitions/1234abcd-1234-abcd-1234-abcd1234abcd
Private endpoint should be enabled for PostgreSQL servers                                /.../policyDefinitions/abcdabcd-1234-abcd-1234-abcd1234abcd
Azure Container Instance container group should use customer-managed key for encryption  /.../policyDefinitions/abcd1234-abcd-1234-abcd-1234abcd1234

Check the Name column for each Azure policy assignment returned by the policy assignment list command output. If the following definition name is not listed in the Name column: Azure AI Services resources should restrict network access, the Azure AI Services resources should restrict network access policy assignment is not implemented within the selected Azure subscription.

05 Repeat steps no. 3 and 4 for each subscription available in your Microsoft Azure cloud account.

Remediation / Resolution

To ensure that only allowed networks can access the Azure AI Foundry resources deployed across your organization, enforce the "Azure AI Services resources should restrict network access" policy assignment, by performing the following operations:

Using Azure Console

01 Sign in to the Microsoft Azure Portal.

02 Navigate to Azure Policy blade available at https://portal.azure.com/#blade/Microsoft_Azure_Policy/PolicyMenuBlade.

03 In the left navigation panel, under Authoring, choose Assignments to access the list with all the initiative and policy assignments available within your Azure account.

04 On the Assignments page, choose Assign policy, and perform the following actions to assign the required policy:

  1. For Basics, provide the following information:
    1. For Scope, choose the Azure subscription that you want to use as policy assignment scope. A scope determines what resources or grouping of resources the policy assignment gets enforced on.
    2. (Optional) For Exclusions, choose the resource group or the cloud resources that can be excluded based on the selected scope. Exclusions start at one level lower than the level of the selected scope (in this case, the selected subscription). For example, at the subscription scope, you can assign a definition that prevents the creation of AI Foundry instances. You can exclude a resource group from the selected subscription that is intended for administration only.
    3. For Policy definition, click on the Browse icon (i.e., ellipsis icon) to open the list of available policy definitions. On the Available Definitions panel, select the built-in definition named Azure AI Services resources should restrict network access and choose Add to add the specified policy definition. This policy ensures that only allowed networks can access the AI Foundry resources. This can be achieved by configuring network rules so that only applications from allowed networks can access the AI Foundry service.
    4. Leave the assignment name unchanged in the Assignment name box.
    5. Provide a short description for the new assignment in the Description text box.
    6. Ensure that Policy enforcement is set to Enabled.
    7. Choose Next to continue the setup process.
  2. For Parameters, specify the required parameters for the selected policy assignment. Choose Next to continue the setup.
  3. (Optional) For Remediation, perform the following actions to create the required system-sassigned managed identity. Policies with the deployIfNotExists and modify effect types need the ability to deploy resources and edit tags on existing resources respectively. To do this, create a new system assigned managed identity:
    1. Select the Create a Managed Identity checkbox.
    2. For Type of Managed Identity, choose System assigned managed identity.
    3. Select the appropriate location from the System assigned identity location dropdown list.
    4. Choose Next to continue the setup.
  4. (Optional) For Non-compliance message, provide a message to help users understand why a resource is not compliant with the policy. Choose Review + create to continue the setup.
  5. Choose Create to deploy the Azure AI Services resources should restrict network access policy assignment to your Azure subscription.

05 Repeat step no. 4 for other subscription available within your Microsoft Azure cloud account.

Using Azure CLI

01 Run account list command (Windows/macOS/Linux) with custom output filters to list the IDs of the cloud subscriptions available in your Azure cloud account: 

az account list
	--query '[*].id'

02 The command output should return the requested subscription identifiers (IDs): 

[
	"abcdabcd-1234-abcd-1234-abcdabcdabcd",
	"abcd1234-abcd-1234-abcd-abcd1234abcd"
]

03 Run policy assignment create command (Windows/macOS/Linux) with the ID of the Azure AI Services resources should restrict network access policy definition as value for the --policy parameter (i.e., 037eea7a-bd0a-46c5-9a66-03aea78705d3), to create a "Not Allowed Resource Types" policy assignment for the selected Azure cloud subscription (scope). In the following command example, the cloud resource type that your organization cannot deploy within the specified scope, defined as value of the -p parameter, is Azure Key Vault: 

az policy assignment create
	--display-name "Azure AI Services resources should restrict network access"
	--policy "037eea7a-bd0a-46c5-9a66-03aea78705d3"
	--scope /subscriptions/abcdabcd-1234-abcd-1234-abcdabcdabcd

04 The command output should return the new Azure policy assignment information: 

{
	"description": null,
	"displayName": "Azure AI Services resources should restrict network access",
	"enforcementMode": "Default",
	"id": "/subscriptions/abcdabcd-1234-abcd-1234-abcdabcdabcd/providers/Microsoft.Authorization/policyAssignments/abcdabcdabcdabcdabcd",
	"identity": null,
	"location": null,
	"metadata": {
		"createdBy": "abcd1234-abcd-1234-abcd-abcd1234abcd",
		"createdOn": "2025-09-08T18:36:21.7302231Z",
		"updatedBy": null,
		"updatedOn": null
	},
	"name": "abcdabcdabcdabcdabcd",
	"nonComplianceMessages": null,
	"notScopes": null,
	"parameters": null,
	"policyDefinitionId": "/providers/Microsoft.Authorization/policyDefinitions/037eea7a-bd0a-46c5-9a66-03aea78705d3",
	"scope": "/subscriptions/abcdabcd-1234-abcd-1234-abcdabcdabcd",
	"systemData": {
		"createdAt": "2025-09-08T18:36:21.703625+00:00",
		"createdBy": "ser@domain.com",
		"createdByType": "User",
		"lastModifiedAt": "2025-09-08T18:36:21.703625+00:00",
		"lastModifiedBy": "user@domain.com",
		"lastModifiedByType": "User"
	},
	"type": "Microsoft.Authorization/policyAssignments"
}

05 Repeat steps no. 3 and 4 for other cloud subscription available in your Microsoft Azure account.

References

Publication date Sep 10, 2025

Related AIServices rules