Information Disclosure Vulnerability in M365 Copilot by Microsoft
CVE-2026-54130

9.8CRITICAL

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Copilot
Vendor
CVE Published:
18 June 2026

What is CVE-2026-54130?

A significant vulnerability in M365 Copilot allows unauthorized attackers to potentially disclose sensitive information over a network due to a lack of proper authentication for critical functions. This oversight can be exploited to gain access to confidential data, posing serious risks to user privacy and organizational security.

Affected Version(s)

Microsoft 365 Copilot -

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
9.8
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.