CVE-2025-21088

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 validate the style of proto supplied to an action's style in post.props.attachments, which allows an attacker to crash the frontend via crafted malicious input.

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

30 Sep 2025, 15:52

Type	Values Removed	Values Added
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
CPE		cpe:2.3:a:mattermost:mattermost_server:::::::: cpe:2.3:a:mattermost:mattermost_server:10.2.0:-::::::
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 logran validar correctamente el estilo del proto suministrado al estilo de una acción en post.props.attachments, lo que permite que un atacante bloquee el frontend a través de una entrada maliciosa manipulada.
First Time		Mattermost Mattermost mattermost Server

15 Jan 2025, 16:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-01-15 16:15

Updated : 2025-09-30 15:52

NVD link : CVE-2025-21088

Mitre link : CVE-2025-21088

CVE.ORG link : CVE-2025-21088

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-704

Incorrect Type Conversion or Cast

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