Azure Active Directory (Azure AD) Conditional Access is a cloud-based identity and access management service that lets you control access to your cloud apps and data. It allows you to enforce organizational policies, such as requiring multi-factor authentication (MFA) or limiting session duration, based on specific conditions.

What is Conditional Access?

Conditional Access policies provide a centralized way to manage access to all your cloud applications. Instead of configuring access controls for each application individually, you can use Conditional Access to create a single policy that is enforced for multiple applications.

Key Components of a Conditional Access Policy:

  • Assignments: Define who the policy applies to (users, groups, or applications).
  • Conditions: Specify the context under which the policy is enforced (e.g., user location, device platform, application, sign-in risk).
  • Access controls: Determine what actions are allowed or blocked (e.g., grant access, require MFA, require device compliance, limit session).

Common Use Cases:

1. Require Multi-Factor Authentication (MFA) for All Users

A foundational policy to enhance security by ensuring users verify their identity with more than just a password.

Recommendation: Implement MFA broadly across your organization to mitigate credential compromise risks.

2. Block Access from Untrusted Locations

Prevent access to sensitive applications when users are signing in from IP addresses that are not recognized as safe or trusted by your organization.

3. Require Compliant Devices for Access to Corporate Resources

Ensure that only devices managed and compliant with your organization's security policies can access company data.

4. Limit Session Duration for Sensitive Applications

Reduce the risk of unauthorized access if a device is lost or stolen by enforcing shorter session lifetimes.

How to Create a Conditional Access Policy:

  1. Navigate to the Azure Active Directory portal.
  2. Under 'Security', select 'Conditional Access'.
  3. Click 'New policy'.
  4. Configure the 'Assignments' (Users and groups, Cloud apps or actions).
  5. Define the 'Conditions' (Sign-in risk, User risk, Device platforms, Locations, Client applications, etc.).
  6. Configure the 'Access controls' (Grant, Session).
  7. Enable the policy and save your changes.

It is highly recommended to start with a 'Report-only' mode to understand the impact of your policies before enforcing them.

Caution: Incorrectly configured policies can lock users out of resources. Always test thoroughly.

Best Practices:

  • Start with Report-only Mode: Monitor the effects before enforcement.
  • Use Named Locations: Define trusted IP address ranges for your organization.
  • Require Compliant Devices: Integrate with Microsoft Intune or other Mobile Device Management (MDM) solutions.
  • Regularly Review Policies: Ensure they align with current security needs.
  • Exclude Emergency Access Accounts: Create at least one emergency access account (break-glass account) that is excluded from all Conditional Access policies to prevent accidental lockout.

Conditional Access is a powerful tool for securing your cloud environment. By implementing well-defined policies, you can significantly reduce your organization's attack surface and protect sensitive data.