CVE-2025-9076

Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.

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)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

History

19 Oct 2026, 17:10

Type	Values Removed	Values Added
Summary		(es) Mattermost versiones 10.10.x menor o igual que 10.10.1 no logran sanear correctamente los datos de usuario durante la sincronización de membresía de canales compartidos, lo que permite a clústeres remotos maliciosos o comprometidos acceder a información sensible del usuario a través de objetos de usuario no saneados. Esta vulnerabilidad afecta a instancias del servidor Mattermost con canales compartidos habilitados.

Information

Published : 2025-09-15 10:15

Updated : 2026-10-19 17:10

NVD link : CVE-2025-9076

Mitre link : CVE-2025-9076

CVE.ORG link : CVE-2025-9076

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-862

Missing Authorization

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