Introduction

In today’s cybersecurity landscape, proper management of privileged accounts in Active Directory (AD) environments is not just a best practice—it’s a critical security requirement. The principle of least privilege and the implementation of proper account lifecycle management can mean the difference between a secure environment and a potential security breach. This article explores the importance of Active Directory delegation models, privileged account management, and introduces an automated solution for maintaining account hygiene.

The Active Directory Delegation Model: Foundation of Security

Understanding the Tiered Model

Microsoft’s security recommendation emphasizes the importance of administrative tier separation (and still current while On-Prem hybrid implementation):

• Tier 0: Domain controllers, domain admin accounts, and other identity infrastructure
• Tier 1: Server administrators and server management accounts
• Tier 2: Workstation administrators and user management accounts

This model ensures that administrative credentials from lower tiers cannot compromise higher tiers, preventing lateral movement and privilege escalation attacks.

The Privileged Account Challenge

Organizations often struggle with privileged account proliferation—the uncontrolled growth of accounts with elevated permissions. Common issues include:

1. Orphaned Accounts: Privileged accounts that remain active after the associated user leaves the organization
2. Stale Accounts: Administrative accounts that are no longer needed but remain enabled
3. Inconsistent Lifecycle Management: Lack of automated processes to manage account creation, modification, and deletion
4. Audit Compliance: Difficulty in demonstrating proper access controls to auditors

The Semi-Privileged User Concept

What are Semi-Privileged Users?

Semi-privileged users are administrative accounts that possess elevated permissions but are tied to a corresponding non-privileged (standard) user account. This approach provides several benefits:

• Accountability: Clear association between administrative actions and individual users
• Lifecycle Management: Administrative accounts automatically follow the lifecycle of the associated standard user
• Audit Trail: Enhanced ability to track administrative activities back to specific individuals

Implementation Strategy

The key to successful semi-privileged user implementation lies in establishing a clear relationship between accounts. In the solution presented, this relationship is maintained by storing the Security Identifier (SID) of the non-privileged user in the employeeNumber attribute of the semi-privileged account.

Real-World Scenarios

Scenario 1: Employee Departure

Challenge: John Smith, a database administrator, leaves the company. His standard user account (jsmith) is disabled according to HR procedures, but his privileged account (jsmith-admin) remains active with elevated database permissions.

Solution: The automated function identifies that the non-privileged account is disabled and automatically disables the corresponding semi-privileged account, preventing unauthorized access.

Scenario 2: Contractor Account Cleanup

Challenge: Multiple contractor accounts were created for a project that ended six months ago. The contractors’ standard accounts were deleted, but their administrative accounts remain in the system.

Solution: The function detects orphaned administrative accounts (where the linked standard user no longer exists) and marks them for deletion after proper approval workflow.

Scenario 3: Role Change

Challenge: Sarah Johnson moves from IT Operations to Marketing. Her standard account is moved to the Marketing OU and permissions are adjusted, but her server administrative account remains active.

Solution: When the associated non-privileged account is disabled or deleted as part of the role change process, the semi-privileged account is automatically handled according to organizational policy.

Introducing the EguibarIT.HousekeepingPS Module

The Set-SemiPrivilegedKeyPairCheck function is part of the comprehensive EguibarIT.HousekeepingPS PowerShell module, designed specifically for Active Directory housekeeping and security management tasks.

Key Features

• Automated Account Lifecycle Management: Ensures privileged accounts don’t outlive their purpose
• Flexible Exclusion Lists: Protects critical system accounts from automated processing
• Comprehensive Logging: Detailed verbose output for audit and compliance purposes
• WhatIf Support: Safe testing of operations before implementation
• Progress Tracking: Real-time progress reporting for large-scale operations

Function Capabilities

Best Practices for Implementation

1. Establish Clear Policies

Before implementing automated account management:

• Define account naming conventions
• Establish approval workflows for account deletion
• Document exception handling procedures
• Create regular review cycles

2. Start with Monitoring

Begin with read-only operations to understand your current environment:

3. Implement Gradually

Roll out the solution in phases:

1. Phase 1: Test in development environment
2. Phase 2: Implement in non-production with limited scope
3. Phase 3: Full production deployment with comprehensive monitoring

4. Monitor and Audit

Regularly review the function’s output and maintain audit logs:

• Track disabled and deleted accounts
• Review exclusion lists periodically
• Validate that account relationships remain accurate

Security Benefits

Reduced Attack Surface

By automatically managing privileged account lifecycle, organizations significantly reduce their attack surface:

• Fewer Active Privileged Accounts: Only accounts with valid business purposes remain active
• Consistent Policy Enforcement: Automated processes ensure policies are applied uniformly
• Rapid Response: Immediate action when standard accounts are disabled

Compliance and Auditing

Automated account management supports various compliance frameworks:

• SOX: Demonstrates proper access controls and segregation of duties
• GDPR: Ensures timely removal of access when employees leave
• ISO 27001: Supports access management and review processes

Getting Started

Installation

The EguibarIT.HousekeepingPS module is available on GitHub and can be easily integrated into your environment:

Contributing to the Project

The EguibarIT.HousekeepingPS module is an open-source project that welcomes community contributions. Whether you’re:

• Reporting Issues: Help identify bugs or suggest improvements
• Contributing Code: Submit pull requests with new features or fixes
• Sharing Use Cases: Document your implementation experiences
• Improving Documentation: Help make the module more accessible

Visit https://github.com/vreguibar/EguibarIT.HousekeepingPS to get involved.

Conclusion

Proper management of privileged accounts is fundamental to maintaining a secure Active Directory environment. The principle that privileged and semi-privileged users should only exist when associated with valid non-privileged accounts provides a strong foundation for account lifecycle management.

The Set-SemiPrivilegedKeyPairCheck function, part of the EguibarIT.HousekeepingPS module, offers organizations a practical, automated solution for maintaining this security principle. By implementing such tools, organizations can:

• Reduce security risks through automated account lifecycle management
• Improve compliance posture with consistent policy enforcement
• Enhance operational efficiency by reducing manual administrative tasks
• Maintain better audit trails and accountability

As cyber threats continue to evolve, proactive security measures like automated privileged account management become increasingly critical. The investment in proper tooling and processes today can prevent significant security incidents tomorrow.

References and Further Reading

1. Microsoft Security Best Practices:

• Microsoft’s Enhanced Security Administrative Environment (ESAE)
• Active Directory Administrative Tier Model

1. NIST Guidelines:

• NIST Special Publication 800-53: Security Controls for Federal Information Systems
• NIST Cybersecurity Framework

1. Industry Standards:

• CIS Controls v8
• ISO/IEC 27001:2013 Information Security Management

1. PowerShell and Active Directory:

• Active Directory PowerShell Module Documentation
• PowerShell Security Best Practices

1. Community Resources:

• EguibarIT.HousekeepingPS GitHub Repository
• PowerShell Gallery

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For questions, contributions, or support regarding the EguibarIT.HousekeepingPS module, please visit the GitHub repository at https://github.com/vreguibar/EguibarIT.HousekeepingPS or open an issue for community discussion.