CVE-2025-6226

Name of the Vulnerable Software and Affected Versions Mattermost versions 9.11.x through 9.11.16 Mattermost versions 10.5.x through 10.5.6 Mattermost versions 10.7.x through 10.7.3 Mattermost versions 10.8.x through 10.8.1

Description The software fails to verify authorization when retrieving cached posts by PendingPostID. This allows an authenticated user to read posts in private channels they do not have access to by guessing the PendingPostID of recently created posts.

Recommendations Update Mattermost to a version later than 9.11.16. Update Mattermost to a version later than 10.5.6. Update Mattermost to a version later than 10.7.3. Update Mattermost to a version later than 10.8.1.