CVE-2024-4195: Mattermost Server

Low severity, CVSS 2.7. EPSS: 0.5% chance of exploitation in the next 30 days.

Mattermost versions 9.6.0, 9.5.x before 9.5.3, and 8.1.x before 8.1.12 fail to fully validate role changes, which allows an attacker authenticated as a team admin to promote guests to team admins via crafted HTTP requests.

Affected products

• Mattermost Mattermost Server: from 8.1.0, before 8.1.12 (fixed in 8.1.12); from 9.5.0, before 9.5.3 (fixed in 9.5.3)

Published 2024-04-26. Last modified 2026-06-17.