Microsoft 365 Copilot: Maximizing benefits, minimizing data risks

Microsoft Copilot for Microsoft 365 is a sophisticated GenAI engine architected with intertwined components, such as large language models (LLMs), Microsoft Graph content (emails, chats and documents) and essential Microsoft 365 apps (Word, Excel and PowerPoint). This transformative digital assistant empowers users with unparalleled AI-driven productivity, delivering personalized, relevant and actionable responses. Copilot revolutionizes efficiency and elevates the user experience. However, you must implement this groundbreaking digital assistant with caution to mitigate potential risks of sensitive data exposure.

Data security considerations associated with Copilot for Microsoft 365

Like any GenAI tool, Copilot comes with some challenges, including hallucination, data privacy, data accuracy and data readiness. The strength of Copilot is its commitment to preserving user access rights. It diligently operates within the boundaries of the files and documents that users can access. However, if sensitive documents and files are shared excessively, Copilot may inadvertently gain access to them and generate responses that reveal confidential information.

If your organization is considering a Copilot implementation, it’s important to address data classification considerations:

Internal exposure of confidential data. Copilot has access to emails, chats, documents and other data. If confidential data is unintentionally accessible to a wider audience within your organization, it can expose sensitive data to unauthorized users. When malicious insiders or threat actors exploit easily accessible data it can cause financial loss, legal liability and reputational damage.

Improper sensitivity labels. Failing to adhere to proper sensitivity labeling practices exposes your sensitive data to potential mishandling and data breaches. Copilot-generated content amplifies this risk because it inherits labels from referenced files. The challenge is maintaining consistent labeling and limiting unauthorized exposure of sensitive data.

You should also consider user access and endpoint compliance aspects:

Insider threats. Individuals within your organization who have access to data and systems pose insider threats, whether intentionally or unintentionally. They can harm your organization by stealing data, deleting files or granting unauthorized system access to external parties. Copilot respects users' access permissions, but without properly implemented access permissions it might access unauthorized information. This access increases the risk of confidential data or intellectual property (IP) leaks. To safeguard your organization, implement robust security measures like role-based access control (RBAC), monitoring and logging.

Data exfiltration. Data exfiltration is the unauthorized transfer of data beyond an organization's boundaries. It poses risks such as information loss, IP theft and financial harm. Copilot users may unintentionally store or share sensitive data in unauthorized locations. To uphold data integrity and prevent exfiltration, implement robust security measures like multifactor authentication (MFA) to ensure endpoint security and enterprise policy compliance. You should also consider deploying real-time monitoring systems and disabling removable storage access.

Best practices to reap the full benefits of Copilot

To prevent overexposure of your enterprise data while enjoying Copilot's full productivity benefits, consider the following best practices:

Assess data sensitivity classifications. Understand and classify the level of sensitivity of your organization's data using categories like public, internal, confidential and highly confidential. Then set appropriate access permissions and security controls. When you use an existing file as a source in your prompt, Copilot identifies its sensitivity label and shows that label in its response. Incorrect sensitivity labels should be changed.

Conduct a thorough tenant audit. Perform a thorough audit of your Microsoft 365 tenant to identify sensitive data locations. Tools like Microsoft’s Purview Data Loss Prevention (DLP) scanner and the Microsoft 365 Compliance Center will help you discover and classify this data. Review access permissions for files and folders across SharePoint, OneDrive, Exchange Online and Teams. Microsoft 365 administrators can assess SharePoint site access and, after determining whether a site should be accessible to all employees (public) or a select group (private), reset permissions.

Implement robust data governance policies. Establish clear and enforceable data governance policies that define data handling procedures, retention periods and appropriate access levels. Make sure all employees are aware of and adhere to these policies. It minimizes the misuse of data. You can govern file classification by automatically labeling all files saved at certain confidential locations. Any stored files will inherit a sensitivity label by default, ensuring they’re accessible only to the right users.

Maintain vigilant monitoring and auditing. Continuously monitor user activities and system events related to data access, transfers and potential security breaches. Microsoft 365 audit logs, Azure Entra ID audit logs and third-party security tools enable comprehensive monitoring. Regular auditing enhances your ability to detect and respond to suspicious activities swiftly.

Leverage DLP rules. Use the DLP rules in Microsoft Purview to detect, monitor and prevent sensitive data transmission across platforms like email, SharePoint and Teams. Built-in DLP policies are available, or you can create custom policies for your organization. You can protect personally identifiable information by adding sensitivity information types in Microsoft Purview. Options include banking, financial, IT, HR, tax, medical, legal and IP.

Microsoft 365 Copilot is a transformative technology that enhances collaboration and productivity. However, data security is paramount. To harness the full potential of Copilot while providing robust security, you must proactively safeguard data. Regular security assessments, continuous employee education and industry best-practice adherence are essential pillars of an effective data security strategy. If you understand and address the risks associated with Copilot, your business can capitalize on its benefits without compromising the integrity and confidentiality of data assets.

Take your organization’s productivity to the next level. Book a complementary Microsoft 365 Copilot consultation with NTT DATA experts to assess your data readiness, data security, endpoint security and access governance.