CVE-2026-96260

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to enforce a request body size limit during CSRF validation of plugin requests which allows an authenticated user to exhaust server memory and cause a denial of service via a large request body sent to a plugin endpoint.. Mattermost Advisory ID: MMSA-2026-00775

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::::::::

History

07 Oct 2026, 16:37

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

22 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-22 21:17

Updated : 2026-10-07 16:37

NVD link : CVE-2026-96260

Mitre link : CVE-2026-96260

CVE.ORG link : CVE-2026-96260

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-789

Memory Allocation with Excessive Size Value

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