GHSA-c28q-m4gf-vg4q Mattermost doesn't enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation

• Go github.com/mattermost/mattermost-server: >= 11.6.0, < 11.6.1 → fixed in 11.6.1 • Go github.com/mattermost/mattermost-server: >= 11.5.0, < 11.5.5 → fixed in 11.5.5 • Go github.com/mattermost/mattermost-server: >= 10.11.0, < 10.11.17 → fixed in 10.11.17 • Go github.com/mattermost/mattermost/server/v8: >= 8.0.0-20250731163400-5b955468ea1e, < 8.0.0-20260501144115-7d6816abdfd1 → fixed in 8.0.0-20260501144115-7d6816abdfd1

Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Fail to enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation (the check was only applied on update/patch), which allows an authenticated user holding PermissionCreateTeam but not PermissionInviteUser on the resulting team to configure invite-controlled team settings (make the team publicly joinable via open invite and/or constrain membership via allowed domains) that they are not permitted to set on an existing team via POST /api/v4/teams with allow_open_invite: true and/or a non-empty allowed_domains in the request body.. Mattermost Advisory ID: MMSA-2026-00655