CVE-2025-6465: Improper Limitation of a Pathname to a Restricted Directory

Mattermost versions 10.8.x = 10.8.3, 10.5.x = 10.5.8, 10.10.x = 10.10.0, 10.9.x = 10.9.3 fail to sanitize file names which allows users with file upload permission to overwrite file attachment thumbnails via path traversal in file streaming APIs...