CVE-2026-3116

Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589

CVSS v3 4.9 MEDIUM

4.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

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::::::::

History

08 Jun 2026, 12:20

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

30 Mar 2026, 13:26

Type	Values Removed	Values Added
Summary		(es) Las versiones de los plugins de Mattermost <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 no validan el tamaño de las solicitudes entrantes, lo que permite a un atacante autenticado causar interrupción del servicio a través del endpoint de webhook. ID de aviso de Mattermost: MMSA-2026-00589

26 Mar 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-26 17:16

Updated : 2026-06-08 12:20

NVD link : CVE-2026-3116

Mitre link : CVE-2026-3116

CVE.ORG link : CVE-2026-3116

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-400

Uncontrolled Resource Consumption

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