CVE-2026-26133: M365 Copilot Information Disclosure Vulnerability

High severity · published Mar 13, 2026

CVE-2026-26133

M365 Copilot Information Disclosure Vulnerability

7.1

CVSS

0.4%

EPSS

On KEV

Description

AI command injection in M365 Copilot allows an unauthorized attacker to disclose information over a network.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N

Attack vector

Network

Complexity

Low

Privileges

None

User interaction

Required

Confidentiality

High

Integrity

Low

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.4% · higher than 38% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Outlook · Microsoft

before 5.2605.0; before 5.2605.0 · source: NVD

Microsoft 365 Copilot for Android · Microsoft

1.0 before 16.0.19815.10000 · source: vendor

Microsoft 365 Copilot for iOS · Microsoft

1.0 before 2.107.2 · source: vendor

Microsoft Edge for Android · Microsoft

1.0.0 before 145.3800.99 · source: vendor

Microsoft Edge for iOS · Microsoft

1.0.0.0 before 145.3800.99 · source: vendor

Microsoft Excel for Android · Microsoft

16.0.0.0 before 16.0.19822.20038 · source: vendor

Microsoft Excel for iOS · Microsoft

1.0 before 2.106.26020617 · source: vendor

Microsoft Loop for iOS · Microsoft

2.0.0 before 2.106.26020617 · source: vendor

Microsoft OneNote · Microsoft

1.0.0 before 2.106.26020617 · source: vendor

Microsoft OneNote for Android · Microsoft

16.0.1 before 16.0.19725.20142 · source: vendor

Microsoft Outlook for Android · Microsoft

1.0 before 5.2605 · source: vendor

Microsoft Outlook for Mac · Microsoft

1.0.0 before 5.2605 · source: vendor

Affected product

Outlook

Microsoft

All Outlook CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-26133

CVE.org

https://www.cve.org/CVERecord?id=CVE-2026-26133

Vendor Advisory

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26133