Controlling Application Consent in Microsoft 365: Protecting Your Organization from Invisible Risk

As organizations increasingly adopt Microsoft 365 and Teams to support hybrid work, collaboration, and automation, the attack surface inevitably expands. While Microsoft’s ecosystem offers powerful integration capabilities, it also introduces serious risks when user consent to third-party applications is not properly controlled. Without adequate guardrails, users may unknowingly grant broad permissions to apps that harvest data, expose credentials, or misuse AI-powered capabilities in ways that compromise privacy, compliance, or intellectual property.

IT and security leaders must take a proactive stance in managing app consent and integration policies. Failure to do so can quietly erode the organization’s ability to protect sensitive data, maintain governance standards, and control how AI tools interact with business content.

The Risk of User Consent in Entra ID

Microsoft Entra ID (formerly Azure Active Directory) allows users to grant applications permissions to access data and services on their behalf. By default, many tenants are configured to allow users to consent to permissions requested by any app, including those developed outside the organization. These permissions might include access to user profiles, email, calendar data, Teams messages, SharePoint files, and more.

This model introduces substantial risk. A well-crafted phishing email can lure users into installing a malicious app that impersonates a legitimate service. Once consented, these apps can persist silently in the environment, harvesting or exfiltrating data without triggering traditional security controls. Even legitimate third-party applications may over-request permissions, creating unnecessary exposure and compliance challenges.

The proliferation of generative AI-based applications—many of which request broad Graph API access—has only heightened the need to manage user consent tightly. Without oversight, users can unknowingly provide large language models with access to confidential emails, documents, chat history, and contact data. The downstream impact may include data leakage, unintentional model training on proprietary content, and regulatory violations.

Third-Party App Exposure in Microsoft Teams

Microsoft Teams introduces another layer of risk. Users can install and use a wide range of third-party applications from the Teams App Store. While these tools can improve productivity, they also carry risks to privacy, data residency, and shadow IT—especially when unsanctioned tools begin to interact with sensitive chat data or share files with external services.

In many cases, these apps operate outside of formal security review processes, bypassing data classification controls and DLP policies. When AI-driven tools are involved, the risk escalates. For instance, a chatbot that integrates with a third-party language model might process internal strategy discussions or customer data without any form of logging, consent tracking, or encryption guarantees.

Disabling third-party apps in the Teams Admin Center—and only enabling approved apps via policy—is a critical control point for reducing this exposure. It allows IT to enforce app governance, reduce the attack surface, and ensure that only trusted applications operate within the collaboration environment.

Taking Control: Permission Auditing and App Blocking

To mitigate these risks, administrators must begin by reviewing the permissions that have already been granted to applications in their environment. This involves inspecting enterprise applications registered in Entra ID and identifying which ones have user or admin consent.

To review and manage permissions for a specific enterprise application:

1. Navigate to the Microsoft Entra admin center and go to Enterprise Applications.
2. Locate the application in question, then select it to view details.
3. Under Permissions, review the list of delegated and application permissions that have been granted.
4. If any permissions were granted by users and are not aligned with policy, select Remove user consent to revoke access.

To completely block or remove the application from the organization:

1. From the same enterprise application view, go to Properties.
2. Set Enabled for users to sign in to No. This disables access without deleting the application object.

To enforce consent policies globally and prevent future unapproved applications:

1. In the Microsoft Entra admin center, navigate to Consent and permissions under Enterprise Applications.
2. Set Do not allow user consent.

Similarly, in the Teams Admin Center, go to Teams Apps > Manage apps. From here, click Actions (In the top right) > Org-wide app settings > Third-party apps set to “Off”.

Final Thoughts

Uncontrolled application consent and ungoverned third-party app use represent a silent threat to data security, privacy, and compliance. As AI and SaaS ecosystems continue to evolve, the boundaries of your organization’s digital perimeter are increasingly defined by the permissions you allow—often unknowingly.

By disabling broad user consent in Entra, restricting third-party Teams apps, and actively auditing enterprise applications, IT leaders can regain control over how data flows across cloud environments. This is not a matter of convenience—it’s a matter of trust, accountability, and long-term resilience.