CVE-2026-6345

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail prevent disclosure of created user password which allows a malicious attacker to impersonate a user via the use of some of those passwords.. Mattermost Advisory ID: MMSA-2026-00614

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

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

14 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Las versiones de Mattermost 11.5.x menor o igual que 11.5.1, 10.11.x menor o igual que 10.11.13, 11.4.x menor o igual que 11.4.3 fallan en prevenir la divulgación de la contraseña de usuario creada, lo que permite a un atacante malicioso suplantar la identidad de un usuario mediante el uso de algunas de esas contraseñas. ID de Aviso de Mattermost: MMSA-2026-00614

Information

Published : 2026-05-18 09:16

Updated : 2026-10-14 20:10

NVD link : CVE-2026-6345

Mitre link : CVE-2026-6345

CVE.ORG link : CVE-2026-6345

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-522

Insufficiently Protected Credentials

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