CVE-2026-3637

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check the create_post channel permission during post edit operations which allows an authenticated attacker with revoked posting privileges to modify their existing posts via direct API requests to the post update and patch endpoints.. Mattermost Advisory ID: MMSA-2026-00627

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 NONE

Integrity Impact LOW

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

14 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Mattermost versiones 11.5.x menor o igual que 11.5.1, 10.11.x menor o igual que 10.11.13, 11.4.x menor o igual que 11.4.3 no verifican el permiso de canal create_post durante las operaciones de edición de publicaciones, lo que permite a un atacante autenticado con privilegios de publicación revocados modificar sus publicaciones existentes a través de solicitudes directas a la API a los puntos finales de actualización y parche de publicaciones. ID de Aviso de Mattermost: MMSA-2026-00627

Information

Published : 2026-05-18 08:16

Updated : 2026-10-14 20:10

NVD link : CVE-2026-3637

Mitre link : CVE-2026-3637

CVE.ORG link : CVE-2026-3637

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-862

Missing Authorization

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