SCIM for ADFS: Automating user provisioning and authentication

At a growing tech company, the IT team faced a serious security breach. A former employee’s account, left active in a SaaS platform due to manual offboarding gaps, was used to access sensitive customer data. Some employees also retained admin privileges they no longer needed, creating additional security risks.

This is not an isolated case, incomplete offboarding is a common cause of security incidents, with organizations facing unauthorized access due to outdated or unrevoked credentials [source].

The IT team faced challenges due to high employee turnover rates since they needed to maintain access alignment among several cloud applications. The organization required automated solutions for user access management to provide proper system privileges alongside protected security measures.

This write-up explores how SCIM (System for Cross-domain Identity Management) and ADFS (Active Directory Federation Services) work together to automate identity lifecycle management, their security benefits, and best practices for implementation.

SCIM for ADFS: Automating identity lifecycle management

The security breach exposed the IT team to the understanding that manual user access management had reached its limit. Their immediate need was an automated system that could control access provisioning along with deprovisioning so that employees would have appropriate access but not over an extended period.

SCIM and ADFS work together to streamline identity lifecycle management:

• SCIM automates provisioning and deprovisioning by creating, updating, and removing user accounts across SaaS applications
• ADFS provides authentication and Single Sign-On (SSO) so users can log in once with their Active Directory credentials to access multiple applications

How this integration improves identity management

• Automatic access control – Employees only retain access while they are active in the organization
• Seamless offboarding – SCIM automatically revokes access upon offboarding, reducing security risks
• Consistent permissions – Synchronizes access across applications, avoiding manual errors
• Compliance enforcement – Helps organizations meet GDPR, HIPAA, and SOC 2 requirements without manual intervention

By integrating SCIM with ADFS, the IT team eliminated security risks from outdated accounts, enforced centralized access management, and reduced the burden of manual identity administration.

How SCIM complements ADFS

After implementing SCIM, the IT team quickly realized a gap: while SCIM automated user provisioning, it did not handle authentication. Employees still needed a way to securely access applications without managing multiple credentials. This is where Active Directory Federation Services (ADFS) bridges the gap by enabling authenticated access through Single Sign-On (SSO) and centralized authentication.

How they work together

• SCIM operates at the application level, ensuring that user accounts in SaaS applications are created, updated, and removed when changes occur in Active Directory
• The application-level functionality of SCIM enables user account creation and maintenance within SaaS programs as changes happen in Active Directory
• ADFS operates at the directory level, managing authentication by verifying user credentials stored in Active Directory
• SCIM provisions user accounts in SaaS applications when they are added to Active Directory, ensuring user attributes like email, department, and role remain in sync
• ADFS authenticates users and provides SSO access across connected applications by verifying Active Directory credentials
• SCIM removes user accounts from SaaS applications when an employee leaves, preventing unauthorized access
• ADFS revokes login permissions when an account is deactivated in Active Directory, ensuring no lingering access
• The federation server manages authentication, handling security tokens and trust relationships for identity management across federated environments

Why SCIM and ADFS complement each other

SCIM and ADFS eliminate manual account management, reducing security risks, and enforcing consistent access policies.

• SCIM ensures user accounts exist where needed in SaaS applications but does not handle authentication
• ADFS centralizes authentication at the directory level, allowing users to access multiple applications with a single login, reducing the need for repeated authentication
• Authentication is managed through SAML, OAuth, and OpenID Connect protocols, ensuring secure access
• ADFS does not provision users; it relies on SCIM to create, update, and delete user accounts in SaaS applications

By integrating SCIM’s application-level provisioning with ADFS’s directory-level authentication, organizations achieve a seamless and secure identity management experience across cloud and on-premises environments.

How SCIM works with ADFS

Through collaboration between SCIM and ADFS, the IT team achieved automatic user access updates. An automated system processed all changes in Active Directory (AD) through a response sequence to handle user creation and offboard events, which maintained continuous identity management for all applications.

The proxy service plays a critical role in facilitating the integration of ADFS with external applications by enabling single sign-on (SSO) and linking user identity and claim rules between Active Directory and third-party systems.

Step 1: User provisioning in Active Directory

• A new employee account is created in Active Directory (AD)
• SCIM automatically provisions user accounts in connected SaaS applications such as Salesforce, Slack, and ServiceNow, utilizing user credentials stored in the enterprise system
• New employees gain immediate access to the tools they need, eliminating delays caused by manual account creation

Step 2: User authentication via ADFS

• The employee logs into a SaaS application using their AD credentials through ADFS
• ADFS validates the credentials and issues a claims-based authentication token
• Users can seamlessly access multiple applications without entering credentials again

Step 3: Updating user roles and permissions

• When an employee is promoted or moves to a new department, SCIM syncs role changes and manages access requests across applications
• Access permissions update automatically, preventing manual errors and ensuring security policies stay consistent

Step 4: User offboarding and deactivation

• SCIM removes user accounts from all connected applications when an employee leaves.
• ADFS blocks authentication attempts through the federation server proxy, preventing unauthorized access to company resources
• Instant deactivation reduces security risks and compliance violations

Why this matters

By integrating SCIM with ADFS, organizations eliminate manual identity management, improve security, and ensure users always have the right level of access- no more, no less.

Why use SCIM with ADFS?

After struggling with manual provisioning and authentication gaps, the IT team knew they needed a centralized system to manage identities efficiently. SCIM alone automated user provisioning, but authentication remained fragmented across multiple applications. This created security risks, compliance challenges, and additional administrative workload.

By integrating SCIM with ADFS, organizations can:

• Centralize identity management – Ensure that user accounts are automatically synchronized across all applications
• Enable seamless SSO – Employees log in once with Active Directory credentials, eliminating multiple passwords
• Ensure compliance – Automated provisioning and access control help meet GDPR, HIPAA, and SOC 2 standards
• Utilize Microsoft Entra ID – Leverage Microsoft Entra ID as an alternative solution that integrates with SCIM-compliant applications to enhance user management systems and provide robust Single Sign-On (SSO) capabilities

Why SCIM works best with ADFS

While SCIM automates user provisioning across applications, it does not handle authentication on its own. Without ADFS, authentication remains a challenge, requiring users to log in separately to each application and leading to inconsistent access policies.

Challenges of using SCIM without ADFS

• Multiple Logins → Users must authenticate separately for each SaaS application, increasing password fatigue
• No centralized authentication → Access policies vary across applications, making security inconsistent
• Limited IT Control → IT teams cannot enforce uniform authentication standards or manage login mechanisms effectively

How ADFS enhances SCIM

By integrating ADFS with SCIM, organizations get a fully automated identity management system that:

• Eliminates multiple logins → Users authenticate once with Active Directory and gain access to all connected applications through SSO
• Improves security → ADFS enforces centralized authentication policies, Multi-Factor Authentication (MFA), and secure access protocols (SAML, OAuth, OpenID Connect)
• Reduces IT workload → SCIM automates user provisioning and deprovisioning, while ADFS ensures only authorized users can log in

Key benefits of SCIM with ADFS

• Centralized identity management → SCIM keeps all user accounts in sync across applications. Any changes in Active Directory trigger automatic updates, eliminating manual user management
• Stronger access control and compliance → SCIM and ADFS enforce consistent access policies and support compliance with GDPR, HIPAA, and SOC 2 by ensuring:
  
  • Immediate deprovisioning when employees leave
  • Uniform authentication policies across applications
  • Enforced MFA, reducing the risk of unauthorized access
• Simplified and secure authentication → ADFS acts as a single authentication authority, verifying users against Active Directory before granting access to applications. This ensures:
  
  • Faster and seamless access → No need for repeated password entry
  • Stronger security controls → IT teams can centrally enforce authentication policies
  • Efficient identity management → SCIM handles provisioning, while ADFS ensures only authorized users can log in

By using SCIM for provisioning and ADFS for authentication, organizations achieve secure, seamless identity management with reduced security risks and lower administrative overhead.

Security benefits of SCIM with ADFS

Organizations achieve automated identity management security enhancements by integrating SCIM with ADFS. This ensures that authorized users can securely access applications, while departed employees immediately lose access, reducing security risks.

1. Centralized identity control

• Prevents orphaned accounts by automatically deactivating users in all connected applications when they leave the organization
• Ensures consistent access policies across all SaaS platforms

2. Automated user offboarding

• Manual offboarding delays can leave ex-employees with lingering access to business-critical applications
• SCIM instantly removes accounts, and ADFS blocks authentication attempts, preventing unauthorized access

3. Multi-Factor Authentication (MFA) with ADFS

• ADFS does not provide MFA directly but integrates with external MFA providers to enforce an extra verification step, such as OTP, biometric authentication, or hardware tokens
• Strengthens authentication security by reducing phishing risks and protecting against stolen credentials

Organizations achieve improved security and easier management and compliance through the combination of SCIM for provisioning with ADFS to secure authentication.

Security risks & challenges of SCIM with ADFS

Unsecured configurations or controls implemented during SCIM and ADFS deployment may create opportunities for security vulnerabilities to appear. IT teams need to resolve these security risks because overcoming unauthorized access and data breaches, along with compliance violations is essential.

1. API exploits due to weak authentication controls

SCIM relies on APIs to manage user accounts, making it a potential target for attackers. SCIM authentication typically uses bearer tokens, which, if compromised, can allow unauthorized modifications to user data.

If an attacker gains access to a SCIM bearer token, they could:

• Modify user roles and permissions
• Create unauthorized user accounts
• Delete or deactivate existing accounts, disrupting access

Safeguards:

• Use OAuth 2.0 with short-lived tokens instead of static API keys
• Implement IP allowlisting and role-based access control (RBAC) to restrict API usage

2. Orphaned accounts from delayed deprovisioning

Sync errors or misconfigurations can result in ex-employees retaining access to SaaS applications. These orphaned accounts pose a security risk if left unmanaged, increasing the likelihood of unauthorized access.

Safeguards:

• Conduct regular SCIM audits to ensure deactivated users are fully removed
• Implement fallback scripts to manually disable accounts if SCIM provisioning fails

3. Shadow IT risks due to unmanaged SCIM integrations

Some SaaS applications may not enforce SCIM deprovisioning properly, leading to users retaining access outside IT oversight. This creates security gaps where unauthorized access can go undetected.

Safeguards:

• Restrict SCIM integrations to verified and approved applications
• Regularly audit SCIM logs and enforce ADFS authentication policies to maintain security controls

By proactively addressing these risks, organizations can maximize the security benefits of SCIM and ADFS while ensuring strong access control and compliance.

Best practices for secure SCIM implementation

To ensure a secure SCIM and ADFS deployment, IT teams should follow these best practices:

1. Enforce least privilege access

• Grant users only the permissions they need for their roles
• Use ADFS policies to restrict access based on job roles, location, or device

2. Enable MFA

• Require MFA for all high-privilege accounts and critical applications
• Protect against phishing and credential theft by enforcing biometric or OTP-based authentication

3. Monitor SCIM logs for anomalies

• Set up real-time monitoring using tools like Splunk or Azure Sentinel
• Detect unauthorized API access or provisioning failures before they become security incidents

Organizations that adopt the security best practices can utilize SCIM and ADFS for secure automated identity management solutions that minimize potential security risks.

Conclusion

Using SCIM with ADFS streamlines both user provisioning processes and authentication functions, which decreases security vulnerabilities while sustaining regulatory protocols. The SCIM system supports identity lifecycle operations and, when combined with ADFS, users gain access through Single Sign-On authentication, which eliminates time-wasting repeated logins and manual access administration. The combined deployment of SCIM with ADFS stops orphaned accounts by implementing uniform access protocols and adding security benefits from MFA while automatically ending user access.

The risks of vulnerabilities appear through poorly configured systems, insufficient API security measures, and uncontrolled SCIM integration implementations. Organizations need to track SCIM logs alongside enforcing least privilege access and enabling MFA to protect their identity infrastructure. Through the combination of SCIM technology and ADFS, organizations achieve easier identity management while enhancing security measures and maintaining complete control over access permissions.

FAQ

1. What features do Active Directory systems contain regarding SCIM?

Through SCIM in Active Directory, users can synchronize their AD account properties with third-party cloud applications that include Salesforce, Slack, and ServiceNow. The system performs automated account maintenance and automatically creates, updates, and deactivates profiles from Active Directory changes as part of maintaining application synchronization.

2. Does ADFS actually differ from Single Sign-On in terms of operation?

SSO stands as the core principle of Single Sign-On (SSO) that allows users to authenticate once for many application logins without the need for extra authentication steps. ADFS delivers SSO authentication through its evaluation service of user identities, which generates authentication tokens using SAML, OAuth, and OpenID Connect protocols. The functionality resides in Single Sign-On, while ADFS acts as the implementation mechanism for this functionality.

3. Is ADFS on-prem or cloud?

Windows Server-based ADFS operates as an on-premises identity management system that uses Active Directory for authentication functions. The system allows identity federation with cloud applications but remains suitable when organizations need to secure hybrid environments that use on-prem and cloud-based authentication.

4. What happens if SCIM sync fails?

If SCIM sync fails, user data may become outdated or inconsistent across applications, leading to potential security risks. Orphaned accounts may remain active, allowing unauthorized access, or deactivated users may still retain access to critical systems. To prevent this, organizations should enable real-time sync monitoring, implement fallback scripts for manual deprovisioning, and audit SCIM logs to detect and resolve sync failures promptly.

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