CVE-2025-12559

Name of the Vulnerable Software and Affected Versions Mattermost versions 10.5.x through 10.5.12 Mattermost versions 10.11.x through 10.11.4 Mattermost versions 10.12.x through 10.12.1 Mattermost versions 11.0.x through 11.0.2

Description The software does not properly restrict access to team email addresses. Specifically, it fails to ensure that team email addresses are only visible to Team Admins. Any authenticated user can view these email addresses by sending a GET request to the /api/v4/channels/{channel id}/common teams API endpoint. The channel id variable is used in the request.

Recommendations Update Mattermost to a version later than 10.5.12. Update Mattermost to a version later than 10.11.4. Update Mattermost to a version later than 10.12.1. Update Mattermost to a version later than 11.0.2.