CVE-2026-28732

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during command updates which allows an authenticated team member with Manage Own Slash Commands permission to hijack and impersonate existing system or custom slash commands via editing their own slash command trigger to an already-registered trigger through the command update API. Mattermost Advisory ID: MMSA-2026-00597

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 aplican la unicidad del activador de comandos de barra durante las actualizaciones de comandos, lo que permite a un miembro del equipo autenticado con el permiso 'Gestionar mis propios comandos de barra' secuestrar e suplantar comandos de barra del sistema o personalizados existentes mediante la edición del activador de su propio comando de barra a un activador ya registrado a través de la API de actualización de comandos. ID de aviso de Mattermost: MMSA-2026-00597

Information

Published : 2026-05-18 09:16

Updated : 2026-10-14 20:10

NVD link : CVE-2026-28732

Mitre link : CVE-2026-28732

CVE.ORG link : CVE-2026-28732

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-863

Incorrect Authorization

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