Azure Active Directory (Azure AD) Conditional Access is a powerful tool for enforcing granular access controls to your cloud applications. By implementing intelligent policies, you can significantly enhance your organization's security posture. This post outlines some of the key best practices to help you get the most out of Conditional Access.
1. Start with a Baseline and Iterate
It's crucial to avoid overwhelming your users with overly restrictive policies from the outset. A recommended approach is to:
- Report-only mode: Begin by configuring policies in "Report-only" mode. This allows you to monitor the impact of your policies without enforcing them, identifying potential issues before they affect users.
- Phased rollout: Gradually enable policies for specific user groups or applications, starting with less critical ones.
- Monitor and refine: Continuously review sign-in logs and policy impact reports to make necessary adjustments.
2. Leverage Identity Protection
Azure AD Identity Protection provides valuable signals that can be integrated into your Conditional Access policies. Key signals include:
- User risk: Detects if a user account is compromised.
- Sign-in risk: Detects if a sign-in attempt is anomalous (e.g., impossible travel, unfamiliar location).
Using these signals allows you to dynamically enforce controls like multi-factor authentication (MFA) or session restrictions when a higher risk is detected.
3. Enforce Multi-Factor Authentication (MFA)
MFA is one of the most effective controls against identity compromise. Conditional Access makes it easy to enforce MFA for:
- All users: A universal policy for all users accessing any cloud app.
- Specific applications: Require MFA for access to critical applications like Office 365 or custom applications.
- Risky sign-ins: As mentioned above, requiring MFA for high-risk sign-ins.
- Unmanaged devices: Ensure MFA is used when accessing resources from devices not managed by your organization.
4. Manage Device Compliance
Conditional Access can enforce access based on the compliance state of the device. This means:
- Require Hybrid Azure AD joined or Azure AD joined devices: For access to sensitive data.
- Require compliant devices: Leverage Intune or other MDM solutions to ensure devices meet your security standards (e.g., encrypted, updated OS, password protected).
This practice is crucial for protecting sensitive data when accessed from endpoints.
5. Implement Session Controls
Session controls provide granular management over how users interact with cloud apps:
- Sign-in frequency: Control how often users need to re-authenticate.
- Persistent browser session: Allow users to stay signed in after closing and reopening their browser.
- Use application enforced restrictions: For select applications like SharePoint Online, you can restrict download/upload capabilities.
- Block downloads: Prevent users from downloading sensitive data to unmanaged devices.
6. Define Your Cloud Apps Wisely
When creating policies, be specific about which cloud apps they apply to.
- All cloud apps: Use sparingly and with caution.
- Select cloud apps: A more granular and often safer approach. Consider grouping applications with similar security requirements.
- Exclude critical apps: Be mindful of any applications that might be essential for urgent business operations and might be temporarily affected by new policies.
7. Regularly Review and Audit
The security landscape is constantly evolving, and so should your policies. Schedule regular reviews of your Conditional Access policies to:
- Remove outdated policies.
- Update policies based on new threats or business requirements.
- Ensure all policies are still relevant and effective.
- Review sign-in logs for suspicious activity or policy conflicts.
Conclusion
Azure AD Conditional Access is a cornerstone of modern identity and access management. By adopting these best practices, you can build a robust security framework that protects your organization's valuable cloud resources without hindering legitimate user productivity. Remember to always test your policies thoroughly and monitor their impact.