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 /common_teams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549
Exploitability
AV:NAC:HPR:LUI:NScope
S:UImpact
C:LI:NA:N3.1/CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:NOther