CVE-2026-0998

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 and Mattermost Plugin Zoom versions <=1.11.0 fail to validate user identity and post ownership in the {{/api/v1/askPMI}} endpoint which allows unauthorized users to start Zoom meetings as any user and overwrite arbitrary posts via direct API calls with manipulated user IDs and post data.. Mattermost Advisory ID: MMSA-2025-00534

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::::::::
	cpe:2.3:a:mattermost:zoom::::::mattermost::*

History

18 Feb 2026, 20:22

Type	Values Removed	Values Added
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
CPE		cpe:2.3:a:mattermost:zoom::::::mattermost::* cpe:2.3:a:mattermost:mattermost_server::::::::
First Time		Mattermost mattermost Server Mattermost zoom Mattermost

18 Feb 2026, 17:52

Type	Values Removed	Values Added
Summary		(es) Las versiones de Mattermost 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 y las versiones del plugin de Mattermost Zoom <=1.11.0 no validan la identidad del usuario y la propiedad de la publicación en el endpoint {{/api/v1/askPMI}}, lo que permite a usuarios no autorizados iniciar reuniones de Zoom como cualquier usuario y sobrescribir publicaciones arbitrarias a través de llamadas directas a la API con ID de usuario y datos de publicación manipulados. ID de aviso de Mattermost: MMSA-2025-00534

16 Feb 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-16 10:16

Updated : 2026-02-18 20:22

NVD link : CVE-2026-0998

Mitre link : CVE-2026-0998

CVE.ORG link : CVE-2026-0998

JSON object : View

Products Affected

mattermost

mattermost_server
zoom

CWE

CWE-862

Missing Authorization

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