CVE-2026-21535

Severity CVSS v4.0:

Pending analysis

Type:

CWE-284 Improper Access Control

Publication date:

19/02/2026

Last modified:

20/02/2026

Description

Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network.

Impact

Vector 3.x

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

Base Score: 8.20 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

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

Base Score 3.x

8.20

Severity 3.x

HIGH

References to Advisories, Solutions, and Tools

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21535