CVE-2026-26246

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to bound memory allocation when processing PSD image files which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted PSD file. Mattermost Advisory ID: MMSA-2026-00572

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

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::::::::

History

18 Mar 2026, 18:03

Type	Values Removed	Values Added
First Time		Mattermost Mattermost mattermost Server
Summary		(es) Las versiones de Mattermost 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 no logran limitar la asignación de memoria al procesar archivos de imagen PSD, lo que permite a un atacante autenticado causar el agotamiento de la memoria del servidor y denegación de servicio mediante la carga de un archivo PSD especialmente diseñado. ID de Aviso de Mattermost: MMSA-2026-00572
CPE		cpe:2.3:a:mattermost:mattermost_server::::::::
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory

16 Mar 2026, 14:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-16 14:18

Updated : 2026-03-18 18:03

NVD link : CVE-2026-26246

Mitre link : CVE-2026-26246

CVE.ORG link : CVE-2026-26246

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-789

Memory Allocation with Excessive Size Value

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