TL;DR
Microsoft Copilot embeds generative AI directly into Microsoft 365, helping users draft documents, summarize meetings, analyze data, and surface insights across Word, Excel, Outlook, Teams, and SharePoint. By design, Copilot makes existing data easier to access and understand.
That same capability also reshapes the enterprise risk surface.
Microsoft Copilot doesn’t introduce new data access paths on its own. Instead, it amplifies the impact of existing permissions, sharing settings, identities, and integrations. If your Microsoft 365 environment has oversharing, excessive access, or poorly governed integrations, Copilot can make those issues faster and more visible.
This guide explains Microsoft Copilot security through a SaaS and AI security lens, focusing on real risks, native controls, and practical steps to govern Copilot safely at scale.
What is Microsoft Copilot Security?
Microsoft Copilot security refers to the technical controls and governance processes that protect enterprise data when Copilot is enabled across Microsoft 365, Copilot Chat, and Copilot extensibility such as Graph connectors and Copilot Studio agents.Microsoft is responsible for securing the underlying infrastructure and AI models. Organizations are responsible for:
- Managing identity and access in Entra ID
- Governing permissions and sharing across Microsoft 365
- Controlling Copilot extensibility and integrations
- Protecting sensitive data with classification and DLP
- Monitoring Copilot usage and AI driven data access
- Ensuring compliance with regulatory requirements
Copilot security is fundamentally about governing access and exposure.
How Microsoft Copilot Accesses Enterprise Data
Microsoft 365 Copilot retrieves information using Microsoft Graph (Microsoft’s API developer platform that connects multiple services and devices) and the user’s existing permissions. Copilot can summarize and reference content from sources the user is already allowed to access, including:
- Outlook email and calendars
- Teams chats and meetings
- SharePoint and OneDrive files
- Microsoft 365 apps and services
Copilot does not bypass access controls. However, it makes data discovery and aggregation significantly easier, which means permission hygiene becomes critical.Copilot can also reference external systems through Graph connectors and Copilot Studio agents, expanding the scope of data Copilot can interact with if not tightly governed.
Microsoft Copilot Security Risks
AI-Accelerated Oversharing
The most common Copilot risk is not necessarily AI misuse but existing oversharing across SharePoint, OneDrive, and Teams. Files shared broadly, inherited permissions, and nested groups can result in users having access they should not have.
Copilot can surface and summarize that content instantly.
Sensitive Data Exposure Through Prompts and Summaries
Users may ask Copilot to summarize or analyze documents that contain confidential, regulated, or proprietary data. Without proper labeling and DLP, sensitive information can be surfaced in unintended contexts.
Connector and Extensibility Risk
Graph connectors and Copilot Studio agents can bring additional data sources into Copilot. Poorly governed connectors may expand Copilot’s reach into systems that were not designed for AI driven access.
Agent and Automation Governance Gaps
Copilot Studio enables teams to build custom agents and workflows. Without clear ownership and restrictions, agents can be created with overly broad access to data and connectors.
OAuth and App Consent Exposure
If app consent policies are permissive, attackers or malicious apps can gain access to Microsoft 365 data through OAuth permissions. When combined with Copilot, this can increase the blast radius of compromised tokens.
Limited Visibility into AI-Driven Access Patterns
Traditional security reviews often focus on static permissions. Copilot introduces dynamic, AI driven access patterns that require ongoing monitoring to detect unusual usage or exposure.
Built-In Microsoft Controls that Support Copilot Security
Microsoft provides several native capabilities that support Copilot governance:
- Entra ID identity and conditional access controls
- Sensitivity labels and data loss prevention in Microsoft Purview
- Audit logging across Microsoft 365 services
- Copilot Studio environment controls and DLP policies
- Admin controls for Copilot availability and scope
While these features are necessary, they don’t provide an automatic fix for oversharing, excessive permissions, or unmanaged integrations.
Microsoft Copilot Security Best Practices
1. Clean Up Permissions Before Expanding Copilot Use
- Reduce anonymous and organization wide sharing links
- Review SharePoint site and Teams membership
- Remove excessive group nesting and inherited access
2. Classify and Protect Sensitive Content
- Apply sensitivity labels to high value data
- Use DLP to restrict risky sharing and handling
- Align AI usage with internal data policies
3. Govern Copilot Extensibility
- Maintain an inventory of Graph connectors and agents
- Restrict who can create and publish Copilot Studio agents
- Apply DLP policies to connectors and agent environments
4. Lock Down OAuth and App Access
- Restrict user consent where appropriate
- Review enterprise app permissions regularly
- Remove unused apps and revoke stale tokens
5. Monitor Copilot Usage Continuously
- Review audit logs related to Copilot activity
- Investigate unusual access patterns or spikes
- Establish response playbooks for AI related exposure
How Valence Helps Secure Microsoft Copilot
Valence protects organizations from risks created by SaaS and AI sprawl with unified discovery, SSPM, AI security and governance, ITDR, and flexible remediation options.For Microsoft Copilot, Valence helps teams:
- Identify permission sprawl that increases Copilot exposure
- Discover AI usage and shadow AI across SaaS environments
- Detect risky integrations, OAuth grants, and non human identities
- Monitor AI related access risk across Microsoft 365 and beyond
- Extend governance across SaaS and AI platforms, not just Microsoft
Microsoft Copilot Security Checklist
Final Thoughts
Microsoft Copilot fundamentally changes how users discover and interact with data across Microsoft 365. While it doesn’t create new access paths, it makes existing permissions, sharing settings, and integrations far more powerful and far more visible. For most organizations, the real Copilot risk is not the AI itself, but the state of their underlying SaaS environment.
Valence helps security teams understand and govern that exposure. By providing unified visibility into SaaS and AI access, highlighting oversharing and risky integrations, and supporting flexible remediation workflows across Microsoft 365 and the broader SaaS ecosystem, Valence enables teams to adopt Copilot with confidence. Schedule a personalized demo to see how Valence finds and fixes your SaaS and AI risks.
Frequently Asked Questions
1
Is Microsoft Copilot secure for enterprise use?
2
Does Microsoft Copilot bypass Microsoft 365 access controls?
3
What is the biggest security risk with Microsoft Copilot?
4
How do Graph connectors and Copilot Studio agents affect security?
5
Can Microsoft Copilot expose sensitive or regulated data?
6
Who is responsible for Microsoft Copilot security: Microsoft or the organization?
