Active Directory Hardening Guideline

Introduction:

Below is the top 25 technical controls that should be followed for securing Active Directory (AD). This aims to help provide the best practices for deploying and maintaining Windows Server Active Directory environments.

1. Implement Least Privilege Access: Ensure that users and administrators have the minimum necessary permissions to perform their tasks.
2. Regularly Audit Permissions: Conduct regular audits of user and group permissions to detect and correct any unauthorized access.
3. Enable Secure LDAP: Configure Active Directory to use secure LDAP (LDAPS) to encrypt data transferred between the server and clients.
4. Use Strong Password Policies: Enforce strong password policies for all accounts, including password length, complexity, and expiration.
5. Implement Two-Factor Authentication (2FA): Require 2FA for all privileged accounts, such as administrators and service accounts.
6. Secure Domain Controllers: Physically and logically protect domain controllers by placing them in secure locations, using firewalls, and applying the latest security patches.
7. Enable Security Monitoring and Logging: Configure Active Directory to log and monitor security events, including failed logins, account lockouts, and privilege escalations.
8. Implement Group Policy Hardening: Apply security best practices to Group Policy Objects (GPOs), such as disabling legacy protocols and restricting local administrator privileges.
9. Regularly Update and Patch: Keep Active Directory and the underlying operating system up to date with the latest security patches.
10. Disable or Limit NTLM: Minimize the use of NTLM authentication, or disable it entirely if possible, and use Kerberos instead.
11. Configure Account Lockout Policies: Set up account lockout policies to protect against brute-force attacks.
12. Protect Service Accounts: Limit service account permissions, regularly rotate passwords, and enforce the principle of least privilege.
13. Limit the Use of Domain Admin Accounts: Restrict domain admin accounts to a minimum number and use separate, dedicated accounts for daily tasks.
14. Implement Role-Based Access Control (RBAC): Use RBAC to assign permissions based on users’ roles within the organization.
15. Encrypt Traffic with IPSec: Use IPSec to encrypt data communication between domain controllers and other devices on the network.
16. Implement DNS Security: Enable DNSSEC to protect against DNS-based attacks and data tampering.
17. Monitor for Privileged Account Abuse: Continuously monitor for signs of unauthorized access or privilege escalation by privileged accounts.
18. Implement Network Segmentation: Segment the network to limit the scope of an attacker’s lateral movement.
19. Disable Unused Services and Ports: Disable any unused services, protocols, and ports on domain controllers to reduce the attack surface.
20. Enable Security Baselines: Apply security baselines to ensure a consistent security posture across the environment.
21. Deploy Endpoint Protection: Use endpoint protection solutions to detect and remediate malware and other threats on all devices.
22. Implement Sysmon: Deploy Sysmon to collect detailed information about system activity for monitoring and forensic analysis.
23. Regularly Review AD Health: Periodically review the health of the Active Directory environment, including replication, performance, and security.
24. Establish an Incident Response Plan: Develop a plan to respond to security incidents, including containment, investigation, and remediation.
25. Conduct Regular Security Awareness Training: Train users on security best practices, including recognizing phishing attacks, reporting suspicious activity, and protecting sensitive data.

Conclusion:

By following these guidelines and implementing the recommended security controls, can help ensure the safe and secure use of Windows Server Active Directory, reducing the risk of cyberattacks and protecting sensitive data.