Create an app to access Microsoft Defender for Endpoint without a user

This page describes how to create an application to get programmatic access to Defender for Endpoint without a user. If you need programmatic access to Defender for Endpoint on behalf of a user, see Get access with user context. If you are not sure which access you need, see Get started.

Microsoft Defender for Endpoint exposes much of its data and actions through a set of programmatic APIs. Those APIs will help you automate work flows and innovate based on Defender for Endpoint capabilities. The API access requires OAuth2.0 authentication. For more information, see OAuth 2.0 Authorization Code Flow.

In general, you’ll need to take the following steps to use the APIs:

• Create an Azure Active Directory (Azure AD) application.
• Get an access token using this application.
• Use the token to access Defender for Endpoint API.

This article explains how to create an Azure AD application, get an access token to Microsoft Defender for Endpoint, and validate the token.

Create an app

1. Log on to Azure with a user that has the Global Administrator role.
2. Navigate to Azure Active Directory > App registrations > New registration.

   

3. In the registration form, choose a name for your application, and then select wp-signup.php.
4. To enable your app to access Defender for Endpoint and assign it ‘Read all alerts’ permission, on your application page, select API Permissions > Add permission > APIs my organization uses >, type WindowsDefenderATP, and then select WindowsDefenderATP.

    Note

   WindowsDefenderATP does not appear in the original list. Start writing its name in the text box to see it appear.

   

   Select Application permissions > Alert.Read.All, and then select Add permissions.

   

   You need to select the relevant permissions. ‘Read All Alerts’ is only an example. For example:

   • To run advanced queries, select the ‘Run advanced queries’ permission.
   • To isolate a device, select the ‘Isolate machine’ permission.
   • To determine which permission you need, look at the Permissions section in the API you are interested to call.
5. Select Grant consent.

    Note

   Every time you add a permission, you must select Grant consent for the new permission to take effect.

   

6. To add a secret to the application, select Certificates & secrets, add a description to the secret, and then select Add.

    Note

   After you select Add, select copy the generated secret value. You won’t be able to retrieve this value after you leave.

   

7. Write down your application ID and your tenant ID. On your application page, go to Overview and copy the following.

   

8. For Microsoft Defender for Endpoint Partners only. Set your app to be multi-tenanted (available in all tenants after consent). This is required for third-party apps (for example, if you create an app that is intended to run in multiple customers’ tenant). This is not required if you create a service that you want to run in your tenant only (for example, if you create an application for your own usage that will only interact with your own data). To set your app to be multi-tenanted:
   • Go to Authentication, and add https://portal.azure.com as the Redirect URI.
   • On the bottom of the page, under Supported account types, select the Accounts in any organizational directory application consent for your multi-tenant app.

   You need your application to be approved in each tenant where you intend to use it. This is because your application interacts Defender for Endpoint on behalf of your customer.

   You (or your customer if you are writing a third-party app) need to select the consent link and approve your app. The consent should be done with a user who has administrative privileges in Active Directory.

   The consent link is formed as follows:

   httpsCopy

   https://login.microsoftonline.com/common/oauth2/authorize?prompt=consent&client_id=00000000-0000-0000-0000-000000000000&response_type=code&sso_reload=true
   

   Where 00000000-0000-0000-0000-000000000000 is replaced with your application ID.

Done! You have successfully wp-signup.phped an application! See examples below for token acquisition and validation.

Get an access token

For more information on Azure AD tokens, see the Azure AD tutorial.

Use PowerShell

# This script acquires the App Context Token and stores it in the variable $token for later use in the script.
# Paste your Tenant ID, App ID, and App Secret (App key) into the indicated quotes below.

$tenantId = '' ### Paste your tenant ID here
$appId = '' ### Paste your Application ID here
$appSecret = '' ### Paste your Application key here

$resourceAppIdUri = 'https://api.securitycenter.microsoft.com'
$oAuthUri = "https://login.microsoftonline.com/$TenantId/oauth2/token"
$authBody = [Ordered] @{
    resource = "$resourceAppIdUri"
    client_id = "$appId"
    client_secret = "$appSecret"
    grant_type = 'client_credentials'
}
$authResponse = Invoke-RestMethod -Method Post -Uri $oAuthUri -Body $authBody -ErrorAction Stop
$token = $authResponse.access_token

Use C#:

The following code was tested with NuGet Microsoft.IdentityModel.Clients.ActiveDirectory 3.19.8.

1. Create a new console application.
2. Install NuGet Microsoft.IdentityModel.Clients.ActiveDirectory.
3. Add the following:
   C#Copy

   using Microsoft.IdentityModel.Clients.ActiveDirectory;
   

4. Copy and paste the following code in your app (don’t forget to update the three variables: tenantId, appId, appSecret):
   C#Copy

   string tenantId = "00000000-0000-0000-0000-000000000000"; // Paste your own tenant ID here
   string appId = "11111111-1111-1111-1111-111111111111"; // Paste your own app ID here
   string appSecret = "22222222-2222-2222-2222-222222222222"; // Paste your own app secret here for a test, and then store it in a safe place! 
   
   const string authority = "https://login.microsoftonline.com";
   const string wdatpResourceId = "https://api.securitycenter.microsoft.com";
   
   AuthenticationContext auth = new AuthenticationContext($"{authority}/{tenantId}/");
   ClientCredential clientCredential = new ClientCredential(appId, appSecret);
   AuthenticationResult authenticationResult = auth.AcquireTokenAsync(wdatpResourceId, clientCredential).GetAwaiter().GetResult();
   string token = authenticationResult.AccessToken;
   

Use Python

See Get token using Python.

Use Curl

1. Open a command prompt, and set CLIENT_ID to your Azure application ID.
2. Set CLIENT_SECRET to your Azure application secret.
3. Set TENANT_ID to the Azure tenant ID of the customer that wants to use your app to access Defender for Endpoint.
4. Run the following command:
   ConsoleCopy

   curl -i -X POST -H "Content-Type:application/x-www-form-urlencoded" -d "grant_type=client_credentials" -d "client_id=%CLIENT_ID%" -d "scope=https://securitycenter.onmicrosoft.com/windowsatpservice/.default" -d "client_secret=%CLIENT_SECRET%" "https://login.microsoftonline.com/%TENANT_ID%/oauth2/v2.0/token" -k
   

   You will get an answer in the following form:

   ConsoleCopy

   {"token_type":"Bearer","expires_in":3599,"ext_expires_in":0,"access_token":"eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIn <truncated> aWReH7P0s0tjTBX8wGWqJUdDA"}
   

Validate the token

Ensure that you got the correct token:

1. Copy and paste the token you got in the previous step into JWT in order to decode it.
2. Validate that you get a ‘roles’ claim with the desired permissions.

   In the following image, you can see a decoded token acquired from an app with permissions to all of Microsoft Defender for Endpoint’s roles:

   

Use the token to access Microsoft Defender for Endpoint API

1. Choose the API you want to use. For more information, see Supported Defender for Endpoint APIs.
2. Set the authorization header in the http request you send to “Bearer {token}” (Bearer is the authorization scheme).
3. The expiration time of the token is one hour. You can send more than one request with the same token.

The following is an example of sending a request to get a list of alerts using C#:

var httpClient = new HttpClient();

var request = new HttpRequestMessage(HttpMethod.Get, "https://api.securitycenter.microsoft.com/api/alerts");

request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);

var response = httpClient.SendAsync(request).GetAwaiter().GetResult();

// Do something useful with the response

Source : Official Microsoft Brand
Editor by : BEST Antivirus KBS Team