CVE-2025-11777

Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://mattermost.com/security-updates	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::

History

19 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) Las versiones de Mattermost 10.11.x menor o igual que 10.11.3, 10.5.x menor o igual que 10.5.11 no validan correctamente los permisos de membresía de equipo en la API Add Channel Member, lo que permite a usuarios de un equipo acceder a metadatos de usuario e información de membresía de canal de otros equipos a través del endpoint de la API.

Information

Published : 2025-11-13 18:15

Updated : 2026-10-19 13:10

NVD link : CVE-2025-11777

Mitre link : CVE-2025-11777

CVE.ORG link : CVE-2025-11777

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-863

Incorrect Authorization

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