CVE-2026-5308

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to enforce request body size limits on plugin HTTP endpoints which allows an attacker to cause a denial of service via crafted oversized HTTP requests.. Mattermost Advisory ID: MMSA-2026-00646

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

22 May 2026, 17:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-22 11:16

Updated : 2026-05-22 17:19

NVD link : CVE-2026-5308

Mitre link : CVE-2026-5308

CVE.ORG link : CVE-2026-5308

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-400

Uncontrolled Resource Consumption

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