CVE-2026-54130
Received Received - Intake
Missing Authentication in M365 Copilot Exposes Sensitive Data

Publication date: 2026-06-18

Last updated on: 2026-06-18

Assigner: Microsoft Corporation

Description
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.
CVSS Scores
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Meta Information
Published
2026-06-18
Last Modified
2026-06-18
Generated
2026-06-19
AI Q&A
2026-06-19
EPSS Evaluated
N/A
NVD
CVE-2026-54130
EUVD
EUVD-2026-37946
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
microsoft m365_copilot *
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-306 The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
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Executive Summary

This vulnerability involves missing authentication for a critical function in Microsoft 365 Copilot. Because of this lack of authentication, an unauthorized attacker can access and disclose sensitive information over a network.

Impact Analysis

The vulnerability can have severe impacts including unauthorized disclosure of sensitive information. Given the high CVSS score of 9.8, it indicates that an attacker can remotely exploit this issue without any privileges or user interaction, potentially leading to complete confidentiality, integrity, and availability compromise.

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