CVE-2026-3636

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to sanitize team member data when returned via API to users without elevated permissions which allows a user without permissions to get data about team members roles via invoking various team API endpoints.. Mattermost Advisory ID: MMSA-2026-00626

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

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

History

23 Jul 2026, 16:10

Type	Values Removed	Values Added
Summary		(es) Las versiones de Mattermost 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 no logran sanear los datos de los miembros del equipo cuando se devuelven a través de la API a usuarios sin permisos elevados, lo que permite a un usuario sin permisos obtener datos sobre los roles de los miembros del equipo al invocar varios puntos finales de la API del equipo. ID de Aviso de Mattermost: MMSA-2026-00626

22 May 2026, 17:21

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-22 11:16

Updated : 2026-07-23 16:10

NVD link : CVE-2026-3636

Mitre link : CVE-2026-3636

CVE.ORG link : CVE-2026-3636

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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