CVE-2026-20796

Publication date

2026-02-13 10:30:03

Family

Mattermost

State

PUBLISHED

Description

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