CVE-2026-54130
M365 Copilot Information Disclosure Vulnerability
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
M365 Copilot Information Disclosure Vulnerability
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.
- Record
CVE-2026-54130- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - Weakness
- CWE-306
- Updated
- 2026-11-03
EUVDEUVD-2026-37946
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.
- Record
EUVD-2026-37946- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-9cqp-hgpj-49wr
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to...
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.
- Record
GHSA-9cqp-hgpj-49wr- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
NVD
Missing authentication for critical function in M365 Copilot allows an unauthorized attacker to disclose information over a network.
- Record
CVE-2026-54130- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-306
- Updated
- 2026-11-04
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | CVE List, EUVD | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-54130 is a critical vulnerability (CVSS 9.8) in Microsoft 365 Copilot, published June 18, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.08%, the 65th percentile. No source names a fixed version.