CVE-2025-3230: Mattermost Server

Medium severity, CVSS 5.4. EPSS: 0.2% chance of exploitation in the next 30 days.

Mattermost versions 10.7.x <= 10.7.0, 10.6.x <= 10.6.2, 10.5.x <= 10.5.3, 9.11.x <= 9.11.12 fails to properly invalidate personal access tokens upon user deactivation, allowing deactivated users to maintain full system access by exploiting access token validation flaws via continued usage of previously issued tokens.

Affected products

• Mattermost Mattermost Server: from 9.11.0, before 9.11.13 (fixed in 9.11.13); from 10.5.0, before 10.5.4 (fixed in 10.5.4); from 10.6.0, before 10.6.3 (fixed in 10.6.3); from 10.7.0, before 10.7.1 (fixed in 10.7.1)

Published 2025-05-30. Last modified 2026-06-17.