CVE-2026-41100

Severity CVSS v4.0:

Pending analysis

Type:

CWE-284 Improper Access Control

Publication date:

12/05/2026

Last modified:

12/05/2026

Description

Improper access control in M365 Copilot allows an authorized attacker to perform spoofing locally.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.40 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): Low
Availability (A): None

Base Score 3.x

4.40

Severity 3.x

MEDIUM

References to Advisories, Solutions, and Tools

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-41100