Configure an AD decoy account

You can configure a decoy Active Directory (AD) account that appeals to threat actors by appearing as a legitimate user. Activities triggered on this account are considered true positives for breach detection. Configuring this account helps reduce alert noise and decreases the detection time of an active attack on AD accounts within a network.

Before you begin

• Make sure your deployment phase is complete.
• Discuss this feature with your CST to determine if it is right for your organization.

Steps

1. Create an AD decoy account.
2. Configure AD decoy account properties.
3. Configure Azure AD Connect sync filtering.
4. Verify AD decoy account configuration.
5. Provide account information to Arctic Wolf.

Step 1: Create an AD decoy account

If you have any old disabled accounts, you can reuse them as decoy accounts because attributes have populated data, for example, LastLogon and badPwdCount. If not, you can proceed with creating a new account to use as a decoy.

1. From a domain controller (DC) or a device with AD tools installed, open Active Directory Users and Computers.

2. Right-click the Organizational Unit (OU) where you want to create the AD decoy account, and then select New > User.

   Note: We recommend using an OU that is not set to sync to prevent configuration issues and reduce the time required to configure the account.

3. In the dialog, enter account information that matches the standard format for AD users at your company.

   For example, if your User logon name value is FirstnameLastname@company, use the same format for the decoy account. Do not use words like fake or decoy in the account name. If a standard naming convention is unavailable, use an account name like Admin1 or Administrator1.

   Note: The user logon name must be unique to your environment.

4. Make note of the account name to use later.

5. Click Next.

6. Create a password for the account.

7. Select these two checkboxes:

   • User cannot change password
   • Password never expires

8. Click Next.

9. Review your settings, and then click Finish to create the account.

10. Sign in to the AD decoy account to populate AD schema attributes.

Step 2: Configure AD decoy account properties

1. Right-click the new AD decoy account, and then select Properties.

2. Click the Account tab.

3. Click Logon Hours.

4. In the Logon Hours dialog, select the Logon Denied option, and then click OK.

5. In the Account options section, select these checkboxes:

   • Store password using reversible encryption
   • Smart card is required for interactive login

6. Click OK.

7. In the General tab, enter a description such as User must change default password on first login: "P@ssw0rd!”.

8. Click OK to close the dialog and apply the new properties.

9. If you use:

   • A hybrid Microsoft Entra ID (formerly Azure AD) - Proceed to Step 3: Configure Azure AD Connect sync filtering.
   • On-premises AD only - Proceed to Step 4: Verify AD decoy account configuration.

Step 3: Configure Azure AD Connect sync filtering

Do not complete these steps if:

• You are using an OU for the AD decoy account that is not set to sync.
• You do not use a hybrid Microsoft Entra ID (formerly Azure AD).

1. Run these commands to disable the scheduler. This prevents the accidental export of unverified changes.

   import-module ADSync
   Set-ADSyncScheduler -SyncCycleEnabled $False

2. Sign in to the server running Azure AD Connect sync using the appropriate admin account.

3. Click Start > Synchronization Rules Editor.

4. In the Direction list, select Inbound.

5. Click Add New Rule.

6. On the Description page, configure these fields:

   • Name field — Enter a descriptive name for the rule, such as Decoy - Do Not Sync.
   • Connected System — Select the correct forest.
   • Connected System Object Type — Select user.
   • Metaverse Object Type — Select person.
   • Link Type — Select Join.
   • Precedence — Enter a value that isn't currently used by another synchronization rule.

7. Click Next.

8. Click Add clause, and then configure the scoping filter:

   • Attribute — Select UserPrincipalName.
   • Operator — Select EQUAL.
   • Value — Enter the email address of the AD decoy account.

9. Click Add group.

10. Leave the Join rules section empty, and then click Next.

11. Click Add transformation, and then configure these fields:

    • FlowType — Select Constant.
    • Target Attribute — Select cloudFiltered.
    • Source — Enter True.

12. Click Add.

13. Run a full synchronization to complete the configuration:

    1. Click Start > Synchronization Service.
    2. Click Connectors.
    3. In the Connectors list, select the relevant connector.
    4. In the Actions pane, click Run.
    5. In the Run Connector dialog, in the Run profiles section, select Full synchronization.
    6. Click OK.

    When the synchronization completes, the changes are staged to be exported to Microsoft Entra ID (formerly Azure AD).

    Note: For up-to-date information about syncing, verifying, and exporting AD to Microsoft Entra ID (formerly Azure AD), see Apply and verify changes.

14. Before exporting the changes to Microsoft Entra ID (formerly Azure AD), verify that the changes are correct:

    1. On the command line, navigate to %ProgramFiles%\Microsoft Azure AD Sync\bin.

    2. Run this command, where <Name of Connector> is the name of the relevant connector in Synchronization Service:

       csexport "<Name of Connector>" %temp%\export.xml /f:x

       The command generates an export.csv file that contains all changes staged for export.

    3. Review the file to verify the changes, and repeat the configuration steps as needed until the changes are what you expect.

15. Export the verified changes to Microsoft Entra ID (formerly Azure AD):

    1. In the Connectors list in Synchronization Service, select the relevant connector.
    2. In the Actions list, select Run.
    3. In Run profiles, select Export.

16. In Powershell, run this command to re-enable the sync schedule:

    Set-ADSyncScheduler -SyncCycleEnabled $True

Step 4: Verify AD decoy account configuration

1. Prepare the configuration file:

   1. Download the awn-ad-decoy-configure.zip file and move it to an easily-accessible folder on your machine.
   2. Right-click the awn-ad-decoy-configure.zip file, and then select Extract All.
   3. In the Extract Compressed (Zipped) Folders window, browse for a convenient location to extract the contents. For example, a desktop folder.
   4. Verify that Show extracted files when complete is selected.
   5. Select Extract to extract the contents of the zip file to the new awn-ad-decoy-configure folder in the selected destination.

2. Open a PowerShell window as an administrator.

3. In the PowerShell window, use the cd command to navigate to the awn-ad-decoy-configure folder.

4. Run these commands, replacing <username> with the user logon name value from Step 1: Create an AD decoy account.

   Import-Module .\Verify-ADDecoy
   Verify-ADDecoy <username>

   Note: If you receive a warning that says Verify-ADDecoy.ps1 cannot be loaded because running scripts is disabled on this system., check to make sure you are running this as an administrator. You might also need to change your Execution Policy.

5. If any of the Security Setting items fail, open a new PowerShell window and run the previous commands again.

6. Take a screenshot of the dialog that appears. If any of the Security Setting items fail again, return to Step 2: Configure AD decoy account properties.

Step 5: Provide account information to Arctic Wolf

• Contact your Concierge Security® Team to inform them that you have configured an AD decoy account. Include this information:
  • Username — The user logon name of the AD decoy account from Step 1: Create an AD decoy account.
  • The screenshot from the final step of Step 4: Verify AD decoy account configuration.

Arctic Wolf will then provision security monitoring for this application.

Troubleshoot AD decoy account configuration

This information provides solutions for common AD decoy account configuration issues.

Decoy user account validation failed

Possible cause: If you change settings such as logon hours in the same PowerShell session as running the script, PowerShell might require a restart.

Resolution: Restart the PowerShell session by closing and reopening the terminal window, and then try again.

See also

• Active Directory Integrations