entra ID apps

Microsoft Entra ID apps are applications that are integrated with Microsoft Entra ID (the identity and access management service behind Microsoft 365, Azure, and many other Microsoft cloud services). These apps rely on Entra ID for authentication, authorization, and access control.

In a Microsoft 365 tenant, Entra ID apps typically include:

• SaaS applications from the Microsoft Entra application gallery (for example, many third‑party cloud services).
• Custom applications registered in Entra ID (line‑of‑business apps, APIs, AI agents, etc.).
• Enterprise applications that use Entra ID for single sign‑on (SSO) and Conditional Access.

Adding apps to Entra ID lets organizations use capabilities such as:

• Centralized user and app authentication and authorization.
• Single sign‑on (SSO) using federation or passwords.
• Conditional Access and multifactor authentication enforcement.
• User provisioning and synchronization.
• Role‑based access control using Entra ID application roles.
• OAuth authorization to access Microsoft 365 and other APIs.
• Publishing on‑premises apps securely via application proxy.

Because these apps are an access point to organizational data and services, it is important to “lock them down” in a Microsoft 365 tenant for several reasons:

1. Prevent bypass of Entra ID security controls
   Some applications allow local accounts or backup sign‑in methods that bypass Entra ID SSO. If left enabled, users (or attackers) could:

• Keep access to the app after losing Entra ID access or app assignment.
• Sign in without being subject to Conditional Access, MFA, or Entra ID logging. Locking down apps means:
• Identifying apps that allow local or backup credentials and disabling those options.
• Ensuring users can only sign in via Entra ID so all access is governed and logged.

2. Ensure consistent enforcement of Conditional Access and MFA
   When apps are fully integrated and locked to Entra ID sign‑in, policies such as Conditional Access and multifactor authentication apply uniformly. This helps:

• Enforce Zero Trust access controls across all apps.
• Apply user, device, risk, and network‑based conditions before granting access.

3. Centralize access assignment and lifecycle management
   Entra ID supports user and group‑based access assignment and provisioning. Locking down apps to Entra ID enables:

• Central control over who has access to which apps and roles.
• Automatic disabling or deletion of app accounts when users leave or are out of scope.
• Reduced risk of orphaned accounts and excessive privileges.

4. Improve monitoring, auditing, and incident response
   When all app sign‑ins go through Entra ID:

• Sign‑in events appear in Entra ID logs.
• Identity protection and risk‑based policies can detect and respond to suspicious activity. If apps allow local sign‑ins, attackers can attempt to compromise them without appearing in Entra ID logs, reducing visibility.

5. Support Zero Trust and least‑privilege principles
   Entra ID is central to a Zero Trust architecture. Locking down apps ensures:

• Access is granted only after verification and policy evaluation.
• Permissions and roles are managed centrally and can be minimized.
• Special identity types (such as AI agents via Microsoft Entra Agent ID) are constrained to least privilege.

In summary, Entra ID apps are the applications integrated with Microsoft Entra ID for identity and access management. Locking them down in a Microsoft 365 tenant—by forcing Entra‑based sign‑in, disabling local/backup credentials, and using Entra policies and provisioning—reduces attack surface, improves compliance, and ensures consistent, auditable security controls across the app landscape.

References:

• Step 1: Add SaaS apps to Microsoft Entra ID and to the scope of policies
• What is Microsoft Entra?
• Manage access to an application
• Five steps to integrate your apps with Microsoft Entra ID
• Microsoft Entra fundamentals
• Authorization in Microsoft Entra Agent ID