CVE-2026-26129

May 7, 2026, 10:16 p.m.

7.5
High

Description

Improper neutralization of special elements in M365 Copilot allows an unauthorized attacker to disclose information over a network.

Product(s) Impacted

Vendor Product Versions
Microsoft
  • M365 Copilot
  • *

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-138
Improper Neutralization of Special Elements
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as control elements or syntactic markers when they are sent to a downstream component.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a microsoft m365_copilot / / / / / / / /

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26129

Tags

CWE-138
[email protected]
2026-05-07
CVE-2026-26129

CVSS Score

7.5 / 10

CVSS Data - 3.1

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Privileges Required: NONE
  • Scope: UNCHANGED
  • Confidentiality Impact: HIGH
  • Integrity Impact: NONE
  • Availability Impact: NONE

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

    View Vector String

Timeline

Published: May 7, 2026, 10:16 p.m.
Last Modified: May 7, 2026, 10:16 p.m.

Status : Received

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

[email protected]

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.