Author
Colin Smith
What Security Leaders Need to Know
Here’s the reality: agents are already operating in your environment. Most organizations just don’t have full visibility into them yet. If an agent can read SharePoint content, trigger Power Automate workflows, or respond in Teams, it’s effectively a user account. It has access, permissions, and the ability to act at scale.
The difference is speed and scope. An over-permissioned agent doesn’t just introduce risk, it amplifies it.
This guide focuses on where that risk shows up, how to close governance gaps, and how Agent 365 helps you bring agents into the same security model you already trust.
Why AI Agents Are Treated as Users in Microsoft 365
In the cloud, you don’t control the infrastructure, you control who has access to it.
Because cloud services are operated by third-party providers, your security perimeter isn’t defined by hardware anymore. It’s defined by identity.
That shift is already reflected in how organizations approach security today. Most breaches now involve compromised identities, which is why identity and access management (IAM) has become a core part of any security strategy.
Agents are the next step in that evolution.
In Microsoft 365, everything comes back to identity. Agents authenticate using service principals, managed identities, or delegated tokens, similar to other workloads. That’s intentional. Agents need access to do their job. But in many cases, that access was granted before the right guardrails were in place.
In practice, agents:
- Authenticate to Microsoft Graph, SharePoint, Teams, and Exchange
- Execute actions using delegated or application permissions
- Run continuously—often without human oversight
- Operate across large parts of the tenant, not just a single user context
“Agents are already changing how people work, and IDC predicts there will be 1.3 billion agents by 2028.”
At that scale, a misconfigured agent isn’t a small issue, it’s a multiplier.
Where Traditional Security Models Fall Short
Most enterprise security architectures were designed around human users. Conditional access policies, MFA, and anomaly detection all rely on behavioral baselines calibrated for humans. Agents don’t follow those patterns.
- The visibility gap. There’s no single place to see all agents. They’re created across Copilot Studio, Power Platform, third-party tools, or directly on endpoints. Without an inventory, you’re operating blind.
- The access problem. Agents are often granted broad access early on. Because they run continuously, they don’t just hold that access—they use it constantly.
- The monitoring challenge. Traditional alerts rely on unusual behavior. But agents are designed to be automated. High-volume activity at odd hours isn’t suspicious—it’s expected. Monitoring has to shift from activity to intent.
Most teams don’t struggle with the idea of governing agents, they struggle with where to start. This is where having a structured approach makes the difference. Creospark works with security and Microsoft 365 teams to assess current gaps and put a practical governance model in place.
Real World Risk Scenarios in Microsoft 365
These are patterns we’re already seeing across Microsoft 365 environments:
| Scenario | Security Risk | Required Control |
|---|---|---|
| Knowledge agent with broad SharePoint access | Surfaces sensitive content outside intended audience; bypasses information barriers | Scoped, role-based access with least-privilege enforcement via Microsoft Entra |
| Workflow agent automating approvals in Power Automate | Executes high-impact actions at scale without human review or audit trail | Behavioral monitoring, approval gating, and audit logging via Purview |
| Shadow AI agent installed on endpoint | Accesses enterprise data outside IT visibility; creates compliance gap | Endpoint detection and policy enforcement; block unsanctioned agents via Intune |
| Agent operating under delegated user token | Inherits full user permissions; actions attributed to user, not agent | Migrate to application permissions with explicit, scoped consent |
How Microsoft Agent 365 Closes the Gap
Watch: What is Agent 365?
Microsoft Agent 365 brings agents into the same control plane as users—applying the identity, access, and governance model that security teams already operate within Microsoft 365. This is not a new security layer; it is the extension of existing controls to a new class of principal.
“With Agent 365, IT leaders can confidently embrace agentic AI innovation through a unified control plane that provides the capabilities enterprises need to ensure agents are governed, observable, and secure.”
- Single System of Record for All Agents
Agent 365 provides centralized inventory across Microsoft 365, third-party platforms, and endpoints. Every agent—whether deployed centrally or discovered through shadow AI detection—is enumerated, classified, and tracked. You cannot govern what you cannot see. This is where governance starts. - Identity and Ownership by Default
Every agent is assigned a managed identity with a defined owner and business context. Ownership is not assumed—it is enforced. This enables accountability at every layer: who deployed the agent, what it is authorized to do, and who is responsible when it behaves unexpectedly. - Consistent Access Control via Microsoft Entra
Agent permissions are governed through the same Entra ID policies applied to user accounts. Least privilege is not a best practice—it is a default. Permissions are centrally reviewable, revocable, and auditable. Conditional access policies can apply to agents the same way they apply to users. - Behavioral Monitoring in Real Time
Agent 365 tracks what agents do, not just what they can do. Anomaly detection is calibrated against the agent’s defined purpose and historical behavior, enabling security teams to identify scope creep, unusual data access, and unanticipated interactions before they become incidents. - Integrated Data Protection and Auditability
All agent activity is captured in full audit logs, surfaced through Microsoft Purview. Data access is classified in line with sensitivity labels, and compliance evidence is generated continuously—not reconstructed after the fact during an investigation. - Shadow AI Discovery and Remediation
Agent 365 integrates with Microsoft Defender for Endpoint and Intune to detect agents running outside managed environments. Unsanctioned agents are identified, assessed, and either brought under governance or blocked. If an agent interacts with enterprise data, it falls under your compliance obligations—regardless of how it was deployed.
Agent 365 provides the foundation—but getting it implemented correctly is what turns visibility into control. Creospark helps organizations operationalize Agent 365 so it aligns with how your environment is structured today.
What Security Teams Should Do Now
Start simple and build from there:
- Inventory all agents across Microsoft 365, third-party platforms, and endpoints. Use Agent 365 discovery alongside Defender telemetry to build an authoritative list.
- Assign ownership and purpose to every agent. If an agent cannot be assigned an owner with a defined business justification, it should be suspended pending review.
- Audit and right-size permissions using Entra ID access reviews. Apply least privilege and document exceptions with a compensating control.
- Configure behavioral baselines in Agent 365 for each sanctioned agent. Establish alerts for deviations from expected scope, data access patterns, and interaction volume.
- Address shadow AI directly by enabling endpoint detection policies in Intune and configuring Defender for Endpoint to flag unapproved agent activity. Establish a formal intake process for agent deployment requests.
If you’re working through these steps and want to accelerate the process, we can help you prioritize and implement them in a way that fits your environment and governance model.
Frequently Asked Questions
Q: Why are AI agents treated as users in Microsoft 365?
A: Because they authenticate to the Microsoft identity platform and operate under permissions granted to an identity principal. From an access control perspective, an agent with read/write access to SharePoint is indistinguishable from a user with equivalent permissions. The same security controls that govern users must govern agents.
Q: What is the biggest security risk with AI agents in Microsoft 365?
A: Lack of visibility and control. Many agents are deployed without a formal governance process, resulting in untracked identities, over-permissioned access, and no behavioral baseline. This combination creates both data exposure risk and compliance risk.
Q: How does Microsoft Agent 365 manage agents?
A: Agent 365 provides a unified control plane covering agent inventory, identity and ownership assignment, access governance via Microsoft Entra, real-time behavioral monitoring, audit logging through Microsoft Purview, and shadow AI discovery via Defender for Endpoint and Intune integration.
Q: What is shadow AI, and why does it matter for compliance?
A: Shadow AI refers to agents running outside IT-managed environments—typically installed by end users on endpoints or through unsanctioned third-party tools. These agents may still access enterprise data, creating security exposure and regulatory liability that organizations cannot demonstrate control over.
Q: Where should a Microsoft 365 security team start with agent governance?
A: Start with a complete inventory. You cannot apply controls to agents you do not know exist. Use Agent 365 discovery and Defender telemetry to build that list, then layer in ownership, access review, and behavioral monitoring in sequence.
What Changes Now That Agents Are in Your Environment
AI agents are not a future risk. They are already operating in your Microsoft 365 tenant—accessing data, taking action, and creating accountability gaps that compound over time.
What changes is how you manage them.
The organizations that benefit most from agentic AI won’t be the ones that deploy agents fastest. They’ll be the ones that stay in control as they scale. Microsoft Agent 365 makes that possible, not by introducing a new security model, but by extending the one you already trust to a new class of user.
Agents are users. They access your data, operate under your identity model, and fall under your compliance obligations. The security question is not whether to govern them—it is whether you have the visibility to do so.
