Description
Mattermost versions 10.11.x <= 10.11.10 Fail to invalidate cached permalink preview data when a user loses channel access which allows the user to continue viewing private channel content via previously cached permalink previews until cache reset or relogin.. Mattermost Advisory ID: MMSA-2026-00580
Problem types
CWE-672: Operation on a Resource after Expiration or Release
Product status
10.11.0 (semver)
11.4.0
10.11.11
Credits
Joshua Rogers
References
mattermost.com/security-updates (MMSA-2026-00580)