Mattermost Server Shared Channel Membership Synchronization User Data Exposure Vulnerability

A vulnerability exists in Mattermost Server versions 10.10.x prior to 10.10.1, where user data is not properly sanitized during shared channel membership synchronization. This flaw allows malicious or compromised remote clusters to access sensitive user information through unsanitized user objects. The issue affects Mattermost Server instances with shared channels enabled.

Impact

Exploitation of this vulnerability could lead to unauthorized access to sensitive user information.

Remediation

Users can upgrade to Mattermost Server version 10.11.0 to address this vulnerability.