Conditional Access session controls, specifically ‘Sign-in frequency’, is designed for this exact scenario. It allows you to set a reauthentication period for specific applications, cloud apps, or user groups. This provides granular control without requiring users to perform full MFA if their existing session is still valid, aligning with the requirement for minimal overhead while meeting the security mandate.

Creating a custom role with only the precise permissions the applications require is the best practice for adhering to the principle of least privilege. While ‘Directory Readers’ is a built-in role with lower privilege than ‘Global Reader’, it may still grant more access than necessary. A custom role ensures the service principal has exactly the permissions needed for its function, nothing more, providing the highest level of security control.

In the enterprise application properties, under ‘Properties’, there is a ‘User assignment required?’ setting. If this is set to ‘Yes’, then only users or groups explicitly assigned to the app can access it. Merely being in an Azure AD group that is assigned is the correct step, but you must then check the user’s specific assignment status under ‘Users and groups’ to ensure it shows as assigned (‘Yes’). This is a common oversight during application provisioning.

In Azure AD Privileged Identity Management (PIM), you configure these guardrails directly within the settings for each eligible role. Under the role’s ‘Activation’ settings, you can define the maximum activation duration (2 hours) and under the ‘Assignment’ settings, you can require approval from specific individuals or groups (like the CISO). This centralizes the time-bound, approval-based elevation policy for the role.

When using Azure AD Application Proxy, selecting ‘Azure Active Directory’ as the pre-authentication method is correct. The Application Proxy connector will then force users to authenticate against Azure AD first. Upon successful authentication, it creates a Kerberos Constrained Delegation (KCD) ticket or sets application-specific headers (like `X-MS-CLIENT-PRINCIPAL-NAME`) containing the user’s identity, which are passed to the backend legacy application. ‘Passthrough’ does not perform Azure AD auth, and ‘Header-based’ is not a standalone pre-auth method in this context.

Pass-through Authentication (PTA) agents validate user passwords directly against the on-premises Active Directory in real-time. Therefore, if an account is locked on-premises, the PTA agent will immediately deny the authentication request during the sign-in attempt to Azure AD. Password Hash Synchronization alone synchronizes the password hash, but account lockout state is not synced in real-time; PTA provides the immediate response required by the scenario.

The correct approach leverages automation. You can pre-assign a Microsoft 365 license to the Azure AD group that the contractor will be a member of (or to the user object after it syncs). By ensuring Azure AD Connect synchronization runs on a schedule that completes before 9 AM (or by initiating a manual delta sync after the on-premises account is created), the user object will be provisioned in Azure AD and automatically receive the pre-assigned license, ensuring immediate access.

A Conditional Access policy targeting the specific country (as a named location) with a grant control of ‘Require multi-factor authentication’ is the precise solution. This will not block access but will add a layer of security by requiring MFA when a sign-in originates from that location. This allows legitimate access (e.g., an employee traveling) to proceed after providing a second factor, while potentially stopping unauthorized access if the attacker cannot satisfy the MFA requirement.

Azure AD B2B direct connect (specifically for Microsoft 365 collaboration scenarios) and more broadly, cross-tenant access settings in External Identities, allow you to establish trust and define inbound/outbound access policies between two Azure AD organizations. You can configure tenant A to trust users from tenant B, allowing them to access resources in tenant A without creating individual guest user objects, enabling scalable, administrative collaboration.

Conditional Access session controls, specifically ‘Sign-in frequency’, is designed for this exact scenario. It allows you to set a reauthentication period for specific applications, cloud apps, or user groups. This provides granular control without requiring users to perform full MFA if their existing session is still valid, aligning with the requirement for minimal overhead while meeting the security mandate.0