Microsoft Security Response CenterCVE-2026-85887

M365 Copilot Information Disclosure Vulnerability

CriticalVendor CVSS 7.7 / 10 1 CVE Published Sep 17, 2026 at 7:00 AM UTC

Summary

Incorrect permission assignment for critical resource in M365 Copilot allows an authorized attacker to disclose information over a network.

Separate remediation guidance was not included in the collected bulletin.

Sep 17, 2026 at 7:00 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Sep 27, 2026 at 11:11 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Nov 11, 2026 at 2:20 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Details collected from Microsoft Security Response Center.

Official bulletin How SecurityAlert builds this record

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