CVE-2026-8074: Mattermost Server

Low severity, CVSS 3.8. EPSS: 0.3% chance of exploitation in the next 30 days.

Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to enforce bot-specific permission checks on the user active status endpoint, which allows a User Manager with user management write access but no Integrations access to deactivate bot accounts via the PUT /api/v4/users/{id}/active API endpoint.. Mattermost Advisory ID: MMSA-2026-00667

Affected products

• Mattermost Mattermost Server: from 10.11.0, before 10.11.18 (fixed in 10.11.18); from 11.7.0, before 11.7.1 (fixed in 11.7.1)

Published 2026-06-22. Last modified 2026-06-23.