Active Directory Security Best Practices Checklist – A Complete List to Follow

  author
Written By Mohit Jha
Anuraag Singh
Approved By Anuraag Singh 
Published On December 21st, 2023
Reading Time 7 Minutes Reading

Active Directory aka Windows AD, is the centralized facility of business organizations’ IT infrastructure. It ensures smooth business operations by centralizing access control and managing users, computers, and other resources. If the security or AD gets compromised then it can result in a data breach, unauthorized network access, service disruption, Identity theft, reputation damage, and legal and compliance Issues.

Hence, the security of Active Directory remains in the first place when it comes to ensuring a secure network environment and workflow in an organization. 

Table of Content 

    1. Limit the Number of User Privileges and Access Control
    2. Implement Security Policies Using Groups
    3. Secure Administrative & Service Accounts
    4. Implement Strong Password Policies
    5. Turn Off the Print Spooler Service
    6. Disable SMBv1 and restrict NTLM
    7. Regular Backup and Disaster Recovery Plans

What are the Active Directory Security Best Practices to Follow?

Go through the list of top 10 modern AD security checklists and implement them in your Active Directory environment to minimize the chances of network attacks and become more cyber resilience. Furthermore, It will ensure the protection of sensitive data and minimize the risk of unauthorized access and cyber threats.

1. Limit the Number of User Privileges and Access Control

When it comes to breaking the security of Active Directory, the users with excessive privileges are the most vulnerable. Compromising these users, allows attackers to gain various organizational privileges in your AD environment. Which directly affects the security and regulatory compliance requirements. 

Hence it is a best practice to follow the principle of least privilege. There are various roles available in AD, such as 

  • Administrators
  • Domain Admins
  • Domain Naming Master
  • Infrastructure Master
  • PDC Emulator
  • Schema Master
  • Account Operators
  • Backup Operators
  • DHCP Administrators
  • Distributed COM Users
  • DnsAdmins
  • RID Master

Some users need more privileges than others to perform their work operations. If you are responsible for assigning the different roles then you can make sure to grant users only the permissions necessary for their roles. You can also implement access controls, restricting sensitive operations. Which ensures access to authorized personnel only.

2. Implement Security Policies Using Groups

In organizations where there are large numbers of employees. Implementing security policies one by one can be time-consuming and error-prone. You can leverage Group Policy Objects (GPOs).

GPOs are a collection of different settings, that allow administrators to check how the system will behave for a defined group of computers or users. There are three types of GPOs: local, non-local, and starter. Using GPOs to implement security policies such as restricting unauthorized software installations on user machines, and enhancing firewall rules, etc, helps you enforce security settings across the network. 

3. Secure Administrative & Service Accounts

When you create a domain within Active Directory, the local Administrator account automatically gets into the Administrator domain account. It gains default membership in the Domain Admins and Administrators groups of that domain. If the domain serves as the forest root domain, this account also gains membership in the Enterprise Admins group.

To safeguard this crucial account, Microsoft suggests enabling the “Account is sensitive and cannot be delegated” setting. Since administrative and service accounts have comprehensive control and access over AD and Active Directory resources. Hence, a streamlined policy such as strong passwords, unique usernames, and separate administrative workstations, should be there. Moreover,  it is always a best practice to ensure an extra layer of security with MFA. 

4. Implement Strong Password Policies

Since Brute force attacks are the most common ways to compromise the security posture of the AD environment. Hence, It is one of the most important checklists of active directory security best practices to Implement strong password policies. 

Password leaks from cyber attacks not only compromise the security of a network infrastructure but also enable attackers to move freely within the compromised environment. 

Administrators should first start by eliminating the common and weak passwords from AD. Then they should implement stringent password policies, such as minimum length, complexity requirements, and regular password changes. 

A better strategy and best practice is to consider enforcing MFA (multi-factor authentication) to add an extra layer of security.

5. Turn Off the Print Spooler Service

The Print Spooler automatically becomes active and it handles all the printing-related tasks. However, there is a vulnerability associated with it, any authorized user can remotely access this service. Not only this but they can ask for updates on print jobs, and instruct the DC (Domain Controller) to send notifications using unconstrained delegation. 

This opens up the DC’s computer account credentials to potential exposure. Hence, it is a best practice to keep it disabled. To do this you can follow the below steps.

Steps to Turn Off the Print Spooler Service on Windows Server

  • Step 1. Click on the search box located on the taskbar and type in “services.” 
  • Step 2. From the list of results, choose “Services.” 
  • Step 3. Navigate to the “Standards” tab and double-click on “Print Spooler” from the services listed. 
  • Step 4. Opt for the “Stop” option, then confirm by selecting “OK.”

6. Disable SMBv1 and restrict NTLM

Enabling outdated DCs that support SMBv1 puts systems at risk, as Microsoft phased out SMBv1 in 2014 due to its susceptibility to various attacks. While disabling it is recommended, the reluctance to do so lingers in many organizations.

Run the command line below to disable SMBv1

  • Step 1. Open an administrator-elevated PowerShell console.
  • Step 2. Run Set-SmbClientConfiguration -RequireSecuritySignature $false

Likewise, NTLM usage should be restricted despite the potential impact on operations. Although its deactivation might pose challenges, IT leaders must prioritize minimizing its use to bolster security measures.

Steps to restrict NTLM V1 to select servers 

  • Step 1. Open Registry Editor (search for “regedit”).
  • Step 2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Lsa.
  • Step 3. Create a new DWORD called “LmCompatibilityLevel.”
  • Step 4. Set its value from 0 to 5 (e.g., 5 for “Send NTLMv2 response only. Refuse LM NTLM”).
  • Step 5. Save changes and exit the Registry Editor.

7. Regular Backup and Disaster Recovery Plans

Alex Simons, a Microsoft employee, revealed a staggering statistic: a whopping 90% of organizations rely on Windows Active Directory, catering to a staggering 500 million users. However, the grim reality unveils a vulnerability: a staggering 95 million of these accounts fall prey to attacks daily. Recent data paints a concerning picture, highlighting that 5 million Active Directory accounts face assaults every day, while a staggering 1.2 million Azure AD accounts succumb to compromise monthly.

In response to these cyber threats, it is always essential and a best practice to frequently back up and develop comprehensive disaster recovery plans for your Active Directory environment. You should store these backups offline to ensure they stay safe from malware infections. You can use this database for rapid restoration in case of data corruption, accidental deletions, or cyberattacks.

How Can SysTools Help You?

SysTools provides industry-leading Active Directory Migration Tools and Services, which can assist you in events of AD restructuring, consolidation, and merger. We can further help you reconfigure and set up your AD environment as per your custom needs. 

Bringing It All Together

Since AD plays a crucial role in shaping the organization’s network infrastructure, keeping it safe becomes the utmost priority. However, keeping the Active Directory environment safe, seems a massive undertaking. Therefore we have listed out the top 7 modern checklists of Active Directory security best practices to enhance the overall security posture of your AD environment.