Microsoft 365 Copilot summarizes emails labeled confidential

Companies put sensitivity labels and data loss prevention rules on email to keep confidential messages away from automated tools. From late January 2026, Microsoft 365 Copilot Chat ignored them for some messages. It read and summarized labeled emails in users' Sent Items and Drafts folders. Microsoft blamed a code issue, tracked as CW1226324 and first detected on January 21. It began rolling out a fix in early February. BleepingComputer reported the bug on February 18. Microsoft would not say how many customers were affected. A spokesperson said the bug gave no one access to information they were not already authorized to see.