Researchers at Varonis uncovered a one-click attack against Microsoft 365 Copilot, the AI assistant built into Office apps and Outlook. The flaw, named SearchLeak and tracked as CVE-2026-42824, worked by chaining three separate weaknesses: a crafted link could inject instructions into Copilot’s search feature, cause it to quietly read the victim’s emails, calendar events, and OneDrive files, and then smuggle that data out through a clever misuse of Bing’s image-search feature. The whole attack was invisible — while Copilot appeared to be “thinking,” the victim’s private information was already leaving their account.
The good news is that Microsoft patched SearchLeak in early June 2026, and the fix was deployed automatically. No user action is required. This case is a reminder of why keeping your Microsoft 365 subscription and its automatic updates active matters — the AI features in your productivity apps now carry security implications just like any other software.
How to check if you’re affected
Affected versions of Microsoft 365 Copilot Enterprise included all releases before the June 2026 security update (CVE-2026-42824). Microsoft deployed the patch automatically to all commercial tenants — there is nothing you need to install or configure. If your organization uses Microsoft 365 Copilot, the fix is already in place.