Configuring Microsoft Defender for Endpoint Connectors

Microsoft Defender for Endpoint connectors allow Stellar Cyber to ingest logs or issue response actions with Microsoft Defender for Endpoint and add the records to the data lake. There can be any number of Microsoft Defender for Endpoint connectors active.

This connector requires the following Microsoft endpoint security plan: Microsoft Defender for Endpoint Plan 2. To learn about plans, refer to Compare Microsoft endpoint security plans.

There may be two data sources for third party native alerts if you have integrated both Microsoft Defender for Endpoint (this connector) and Windows Defender Antivirus (free version).

If a tenant is using the Microsoft Defender for Endpoint connector and the status of the connector in System | Connectors is green, alerts from Windows Defender Antivirus will be suppressed in order to remove duplicate logs. If the status of the connector is not green, alerts from Windows Defender Antivirus will not be suppressed.

Stellar Cyber connectors with the Collect function (collectors) may skip collecting some data when the ingestion volume is large, which potentially can lead to data loss. This can happen when the processing capacity of the collector is exceeded.

Connector Overview: Microsoft Defender for Endpoint

Capabilities

  • Collect: Yes

  • Respond: Yes

  • Native Alerts Mapped: Yes

  • Runs on: DP

  • Interval: Configurable

Collected Data

Content Type

Index

Locating Records

Alerts

Host

Vulnerabilities

Syslog

 

msg_class:

microsoft_defender_alerts

microsoft_defender_host

microsoft_defender_vulnerabilities

msg_origin.source:

microsoft_defender

msg_origin.vendor:

N/A

msg_origin.category:

endpoint

https://login.microsoftonline.com

<API Endpoint URL>

where <API Endpoint URL> is a variable from the configuration of this connector

Domain

Response Actions

Action

Required Fields

Contain Host

(for Host and Alerts)

microsoft_defender.id (for Host data)

microsoft_defender.machineId (for Alerts data)

The required permission for response actions is Machine.Isolate.

Third Party Native Alert Integration Details

For the Alerts content type, the Microsoft Defender ATP alerts are mapped to the Stellar Cyber Syslog Index.

For details, see Integration of Third Party Native Alerts.

Required Credentials

  • API Endpoint URL, Client ID with the following permissions, Directory ID, and Client Secret:

    • Permissions for Client ID: Alert.Read.All, Machine.Read.All, Vulnerability.Read.All

Locating Records

Use the following to query for records:

  • msg_origin.source: microsoft_defender

  • msg_class: microsoft_defender_alerts

To search the alerts, use the query: msg_class: microsoft_defender_alerts AND (microsoft_defender.detectionSource: WindowsDefenderAv OR microsoft_defender.detectionSource: WindowsDefenderAtp)

               Let us know if you find the above overview useful.

Adding a Microsoft Defender for Endpoint Connector

To add a Microsoft Defender for Endpoint connector:

  1. Create an app
  2. Gather information
  3. Add the connector in Stellar Cyber
  4. Test the connector
  5. Verify ingestion

Creating an App in Microsoft Entra ID

You must create an app in Microsoft Entra ID (formerly Azure Active Directory) that can access Microsoft Defender for Endpoint. Refer to the following article: https://docs.microsoft.com/en-us/windows/security/threat-protection/microsoft-defender-atp/exposed-apis-create-app-webapp. The article has you enable permissions for:

  • Alert.Read.All

You must also enable permissions for:

  • Machine.Read.All

  • Vulnerability.Read.All

Gathering the Microsoft Entra ID Information

The following is the Microsoft Entra ID (formerly Azure AD) information to gather as you create the app:

  • API Endpoint URL—this is the API URL for the server closest to your region:

    • api-us.securitycenter.microsoft.com

    • api-eu.securitycenter.microsoft.com

    • api-uk.securitycenter.microsoft.com

  • Client ID—this is the Application (client) ID

  • Directory ID—this is the Directory (tenant) ID

  • Client Secret—this is the token you generated

Adding the Connector in Stellar Cyber

With the access information handy, you can add a Microsoft Defender for Endpoint connector in Stellar Cyber:

  1. Log in to Stellar Cyber.

  2. Click System | Integration | Connectors. The Connector Overview appears.

  3. Click Create. The General tab of the Add Connector screen appears. The information on this tab cannot be changed after you add the connector.

    The asterisk (*) indicates a required field.

  4. Choose Endpoint Security from the Category drop-down.

  5. Choose Microsoft Defender for Endpoint from the Type drop-down.

  6. Choose the Function: Collect to collect logs; Respond to contain hosts. If you want Respond, choose both Collect and Respond because Respond uses fields present in Alerts and Host data to perform the Contain Host action.

  7. Enter a Name.

    This field does not accept multibyte characters.

  8. Choose a Tenant Name. The Interflow records created by this connector include this tenant name. If you create an automated response action, note that the Tenant for this connector (Collect and Respond) must be within the Tenant for the action. You can use All Tenants or match specific tenants.

  9. Choose the device on which to run the connector.

  10. (Optional) When the Function is Collect, you can create Log Filters. For information, see Managing Log Filters.

  11. Click Next. The Configuration tab appears.

    The asterisk (*) indicates a required field.

  12. Choose the API Endpoint URL for the server closest to your region for the best performance.

  13. Enter the Client ID you copied earlier.

  14. Enter the Directory ID you copied earlier.

  15. Enter the Client Secret you copied earlier.

  16. Enter the Interval (min). This is how often the logs are collected.

    If data is not being pulled, increase the interval, for example, to 10 minutes.

  17. Choose the Content Type you would like to collect. The logs for Alerts, Host, and Vulnerabilities are supported.

  18. Click Next. The final confirmation tab appears.

  19. Click Submit.

    To pull data, a connector must be added to a Data Analyzer profile if it is running on the Data Processor.

The new connector is immediately active.

Testing the Connector

When you add (or edit) a connector, we recommend that you run a test to validate the connectivity parameters you entered. (The test validates only the authentication / connectivity; it does not validate data flow).

For connectors running on a sensor, Stellar Cyber recommends that you allow 30-60 seconds for new or modified configuration details to be propagated to the sensor before performing a test.

  1. Click System | Integrations | Connectors. The Connector Overview appears.

  2. Locate the connector that you added, or modified, or that you want to test.

  3. Click Test at the right side of that row. The test runs immediately.

    Note that you may run only one test at a time.

Stellar Cyber conducts a basic connectivity test for the connector and reports a success or failure result. A successful test indicates that you entered all of the connector information correctly.

To aid troubleshooting your connector, the dialog remains open until you explicitly close it by using the X button. If the test fails, you can select the  button from the same row to review and correct issues.

The connector status is updated every five (5) minutes. A successful test clears the connector status, but if issues persist, the status reverts to failed after a minute.

Repeat the test as needed.

ClosedDisplay sample messages...

Success !

Failure with summary of issue:

Show More example detail:

 

Verifying Ingestion

To verify ingestion:

  1. Click Investigate | Threat Hunting. The Interflow Search tab appears.

  2. Change the Indices to Syslog if you chose the Alerts or Vulnerabilities content type. The table immediately updates to show ingested Interflow records.

  3. Change the Indices to Assets if you chose the Host content type. The table immediately updates to show ingested Interflow records. Also, hosts discovered through this connector show Microsoft Defender for Endpoint as a data source.

If you configured the connector Respond actions, refer to External Actions: Contain Host to understand how to work with the Contain Host feature.