CVE-2026-2458

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate team membership when searching channels which allows a removed team member to enumerate all public channels within a private team via the channel search API endpoint.. Mattermost Advisory ID: MMSA-2025-00568

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::::::::

History

18 Mar 2026, 17:48

Type	Values Removed	Values Added
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
Summary		(es) Versiones de Mattermost 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 no validan correctamente la membresía del equipo al buscar canales, lo que permite a un miembro del equipo eliminado enumerar todos los canales públicos dentro de un equipo privado a través del endpoint de la API de búsqueda de canales. ID de Aviso de Mattermost: MMSA-2025-00568
First Time		Mattermost Mattermost mattermost Server
CPE		cpe:2.3:a:mattermost:mattermost_server::::::::

16 Mar 2026, 14:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-16 14:19

Updated : 2026-03-18 17:48

NVD link : CVE-2026-2458

Mitre link : CVE-2026-2458

CVE.ORG link : CVE-2026-2458

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-862

Missing Authorization

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