SUSE CVE-2026-20796

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

CVE-2026-20796

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

CVE-2026-20796: Time-of-check Time-of-use (TOCTOU) Race Condition

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

CVE-2025-12559: Exposure of Sensitive Information to an Unauthorized Actor

Mattermost versions 11.0.x = 11.0.2, 10.12.x = 10.12.1, 10.11.x = 10.11.4, 10.5.x = 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/channelid/commonteams endpoint...