CVE-2025-41410: Mattermost Server

Medium severity, CVSS 5.4. EPSS: 0.3% chance of exploitation in the next 30 days.

Mattermost versions 10.10.x <= 10.10.2, 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to validate email ownership during Slack import process which allows attackers to create verified user accounts with arbitrary email domains via malicious Slack import data to bypass email-based team access restrictions

Affected products

• Mattermost Mattermost Server: from 10.5.0, before 10.5.11 (fixed in 10.5.11); from 10.10.0, before 10.10.3 (fixed in 10.10.3); from 10.11.0, before 10.11.3 (fixed in 10.11.3)

Published 2025-10-16. Last modified 2026-06-17.