Microsoft says Office bug exposed customers' confidential emails to Copilot AI | TechCrunch
Summary
Microsoft confirmed a bug in its Office software allowed Copilot AI to access and summarize customers' confidential emails, raising significant data privacy concerns.
Why It Matters
This incident highlights vulnerabilities in AI systems that can compromise sensitive information, emphasizing the need for robust data protection measures. As AI tools become more integrated into business processes, understanding their limitations and risks is crucial for organizations relying on these technologies.
Key Takeaways
- A bug in Microsoft Office exposed confidential emails to Copilot AI.
- The issue persisted for weeks, despite existing data loss prevention policies.
- Microsoft is rolling out a fix but has not disclosed the number of affected customers.
- The incident has prompted concerns about AI tools in sensitive environments, such as government institutions.
- Organizations must evaluate AI integrations to safeguard sensitive information.
In Brief Posted: 6:44 AM PST · February 18, 2026 Image Credits:Rafael Henrique/SOPA Images/LightRocket / Getty Images Zack Whittaker Microsoft says Office bug exposed customers’ confidential emails to Copilot AI Microsoft has confirmed that a bug allowed its Copilot AI to summarize customers’ confidential emails for weeks without permission. The bug, first reported by Bleeping Computer, allowed Copilot Chat to read and outline the contents of emails since January, even if customers had data loss prevention policies to prevent ingesting their sensitive information into Microsoft’s large language model. Copilot Chat allows paying Microsoft 365 customers to use the AI-powered chat feature in its Office software products, including Word, Excel, and PowerPoint. Microsoft said the bug, trackable by admins as CW1226324, means that draft and sent email messages “with a confidential label applied are being incorrectly processed by Microsoft 365 Copilot chat.” The tech giant said it began rolling out a fix for the bug earlier in February. A spokesperson for Microsoft did not respond to a request for comment, including a question about how many customers are affected by the bug. Earlier this week, the European Parliament’s IT department told lawmakers that it blocked the built-in AI features on their work-issued devices, citing concerns that the AI tools could upload potentially confidential correspondence to the cloud. Topics AI, AI, chatbot, Copilot, cybersecurity, data protection...
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