CVE-2025-20621

Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly handle posts with attachments containing fields that cannot be cast to a String, which allows an attacker to cause the webapp to crash via creating and sending such a post to a channel.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

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:mattermost_server:10.2.0:-::::::

History

01 Oct 2025, 17:54

Type	Values Removed	Values Added
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
Summary		(es) Las versiones de Mattermost 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 no gestionan adecuadamente las publicaciones con archivos adjuntos que contienen campos que no se pueden convertir a una cadena, lo que permite a un atacante hacer que la aplicación web se bloquee al crear y enviar dicha publicación a un canal.
First Time		Mattermost Mattermost mattermost Server
CPE		cpe:2.3:a:mattermost:mattermost_server:::::::: cpe:2.3:a:mattermost:mattermost_server:10.2.0:-::::::

16 Jan 2025, 19:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-01-16 19:15

Updated : 2025-10-01 17:54

NVD link : CVE-2025-20621

Mitre link : CVE-2025-20621

CVE.ORG link : CVE-2025-20621

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-1287

Improper Validation of Specified Type of Input

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