CVE-2025-13821

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to sanitize sensitive data in WebSocket messages which allows authenticated users to exfiltrate password hashes and MFA secrets via profile nickname updates or email verification events. Mattermost Advisory ID: MMSA-2025-00560

CVSS v3 5.7 MEDIUM

5.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.1 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

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 Feb 2026, 21:44

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

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 no sanean datos sensibles en mensajes de WebSocket, lo que permite a usuarios autenticados exfiltrar hashes de contraseñas y secretos MFA mediante actualizaciones de alias de perfil o eventos de verificación de correo electrónico. ID de aviso de Mattermost: MMSA-2025-00560

16 Feb 2026, 12:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-16 12:16

Updated : 2026-02-18 21:44

NVD link : CVE-2025-13821

Mitre link : CVE-2025-13821

CVE.ORG link : CVE-2025-13821

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

NVD-CWE-noinfo

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