Configure Windows Endpoint monitoring

This article describes how to configure Windows Endpoint Monitoring (WEM) to have Microsoft Defender for IoT selectively and actively probe Windows systems.

WEM can provide more focused and accurate information about your Windows devices, such as service pack levels.

Supported protocols

Currently the only protocol supported for Windows Endpoint Monitoring with Defender for IoT is WMI, Microsoft's standard scripting language for managing Windows systems.

Prerequisites

Make sure that you've completed the prerequisites listed in Configure active monitoring for OT networks, and have confirmed that active monitoring is right for your network.

Before you can configure a WEM scan from your OT sensor console, you'll also need to configure a firewall rule, and WMI domain scanning on your Windows machine.

Configure the required firewall rule

Configure a firewall rule that opens outgoing traffic from the sensor to the scanned subnet by using UDP port 135 and all TCP ports above 1024.

Configure WMI domain scanning

Before you can configure a WEM scan from your sensor, you need to configure WMI domain scanning on the Windows machine you'll be scanning.

This procedure describes how to configure WMI scanning using a Group Policy Object (GPO), updating your firewall settings, defining permissions for your WMI namespace, and defining a local group.

Prerequisites for WMI domain scanning

  • Make sure that the Windows Management Instrumentation service (winmgmt) is in the automatic start mode.
  • Create a user named wmiuser. Make sure this user is a member of the Domain users on your Windows machine.

Configure a Group Policy Object (GPO)

  1. On your Windows machine, create a new GPO named WMIAccess.

  2. Right-click your new WMIAccess GPO and select Edit.

  3. In the Group Policy Management Editor window, select Computer Configuration > Windows Settings > Security Settings > Local Policies > Security Options.

  4. Navigate to and double-click the DCOM: Machine Access Restrictions in Security Descriptor Definition Language (SDDL) syntax policy to open the properties window to the Template Security Policy Setting tab.

    Use the following steps to configure access for this policy:

    1. Select Edit Security and then in the Access Permission dialog, select Add.

    2. In the Enter the object names to select box, enter wmiuser. Select Check Names to verify the setting, and then select OK.

      The wmiuser (wmiuser@DOMAIN.local) is now listed in the Access Permission dialog.

    3. In the Access Permission dialog:

      1. In the Group or user names list, select wmiuser
      2. In the Permissions for ANONYMOUS LOGON box below, select Allow for both Local Access and Remote Access.

      Select OK to close the Access Permissions dialog.

  5. Back in the Group Policy Management Editor window, make sure that you have Computer Configuration > Windows Settings > Security Settings > Local Policies > Security Options selected.

  6. Navigate to and double-click the DCOM: Machine Launch Restrictions in Security Descriptor Definition Language (SDDL) syntax policy to open the properties window to the Template Security Policy Setting tab.

    Use the following steps to configure access for this policy:

    1. Select Edit Security and then in the Access Permission dialog, select Add.

    2. In the Enter the object names to select box, enter wmiuser. Select Check Names to verify the setting, and then select OK.

      The wmiuser (wmiuser@DOMAIN.local) is now listed in the Access Permission dialog.

    3. In the Access Permission dialog:

      1. In the Group or user names list, select wmiuser
      2. In the Permissions for Administrators box below, select Allow for the Local Launch, Remote Launch, Local Activation, and Remote Activation options.

      Select OK to close the Access Permissions dialog.

Configure your firewall

  1. Navigate back to your WMIAccess GPO you'd created earlier, and select Edit.

  2. In the Group Policy Management Editor dialog, go to Computer Configuration > Windows Settings > Security Settings and expand the Windows Defender Firewall with Advanced Security node.

  3. Under Windows Defender Firewall with Advanced Security, right-click Inbound Rules and select New Rule...

  4. In the New Inbound Rule Wizard, select Predefined and then select Windows Management Instrumentation from the drop-down menu.

  5. Select Next to continue. In the Predefined Rules pane, make sure that all rules in the Rules box are selected.

  6. Select Next to continue, and then select Allow the connection > Finish.

Configure permissions for your WMI namespace

This procedure describes how to define permissions for your WMI namespace, and cannot be completed with a regular GPO.

If you'll be using a non-admin account to run your WEM scans, this procedure is critical and must be performed exactly as instructed to allow sign-in attempts using WMI.

  1. On your Windows machine, open a Run dialog and enter wmimgmt.msc.

  2. In the wmimgmt - [Console Root\WMI Control (Local)] dialog, right-click WMI Control (Local) and select Properties.

  3. In the WMI Control (Local) Properties dialog, select the Security tab > Root > Security.

  4. In the Security for ROOT\SECURITY dialog, make sure that the wmiuser account is listed in the Group or user names box:

    1. Select Add, and in the Enter the object names to select box, enter wmiuser.
    2. Select Check Names > OK.
  5. In the Group or user names box, select the wmiuser account. In the Permissions for Authenticated Users box below, select Allow for the following permissions:

    • Execute Methods
    • Enable Account
    • Remote Enable
    • Read Security
  6. In the Security for ROOT\SECURITY dialog, select Advanced. Then, in the Advanced Security Settings for Root dialog, select the wmiuser account > Edit.

  7. In the Permissions Entry for Root dialog, from the Apply To drop-down menu, select This namespace and all subnamespaces.

    Note

    You must apply permissions recursively to the entire tree.

  8. Select OK until all dialog boxes you'd opened in this procedure are closed.

Add your wmiuser account to the local Performance Log Users group

  1. Sign in to your Windows machine with a user you know is part of the Performance Log Users group.

  2. Open a Run dialog and enter compmgmt.msc.

  3. In the Computer Management dialog, select Computer Management (Local) > System Tools > Local Users and Groups > Groups and double-click Performance Log Users.

  4. Select Add and then, in the Enter the object names to select, enter wmiuser to add the wmiuser to the group. Select Check Names and then OK until all dialog boxes you'd opened in this procedure are closed.

Configure a WEM scan on your sensor console

To configure a WEM scan:

  1. On your OT sensor console, select System settings> Network monitoring > Active discovery > Windows Endpoint Monitoring (WMI).

  2. In the Edit scan ranges configuration section, enter the ranges you want to scan and add the username and password required to access those resources.

    • We recommend enter values with domain or local administrator privileges for the best scanning results.
    • Select Import ranges to import a CSV file with a set of ranges you want to scan. Make sure your CSV file includes the following data: FROM, TO, USER, PASSWORD, DISABLE, where DISABLE is defined as TRUE/FALSE.
    • To get a csv list of all ranges currently configured for WEM scans, select Export ranges.
  3. In the Scan will run area, define whether you want to run the scan in in intervals, every few hours, or by a specific time. If you select By specific time, an additional Add scan time option appears, which you can use to configure several scans running at specific times.

    While you can configure your WEM scan to run as often as you like, only one WEM scan can run at a time.

  4. Select Save and then do one of the following:

    • To run your scan manually now, select Apply changes > Manually scan.

    • To let your scan run later as configured, select Apply changes and then close the pane as needed.

To view scan results:

  1. When your scan is finished, go back to the System settings> Network monitoring > Active discovery > Windows Endpoint Monitoring (WMI) page on your sensor console.

  2. Select View Scan Results. A .csv file with the scan results is downloaded to your computer.

Next steps

Learn more about active monitoring options. For more information, see: