CVE-2026-3114

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate decompressed archive entry sizes during file extraction which allows authenticated users with file upload permissions to cause a denial of service via crafted zip archives containing highly compressed entries (zip bombs) that exhaust server memory.. Mattermost Advisory ID: MMSA-2026-00598

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:11.4.0:::::::*

History

30 Mar 2026, 19:40

Type	Values Removed	Values Added
CPE		cpe:2.3:a:mattermost:mattermost_server:11.4.0:::::::* cpe:2.3:a:mattermost:mattermost_server::::::::
First Time		Mattermost Mattermost mattermost Server
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory

30 Mar 2026, 13:26

Type	Values Removed	Values Added
Summary		(es) Las versiones de Mattermost 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 no validan los tamaños de las entradas de archivo descomprimidas durante la extracción de archivos, lo que permite a usuarios autenticados con permisos de carga de archivos causar una denegación de servicio mediante archivos zip manipulados que contienen entradas altamente comprimidas (bombas zip) que agotan la memoria del servidor. ID de aviso de Mattermost: MMSA-2026-00598

26 Mar 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-26 17:16

Updated : 2026-03-30 19:40

NVD link : CVE-2026-3114

Mitre link : CVE-2026-3114

CVE.ORG link : CVE-2026-3114

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

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