CVE-2026-6689

published 2026-06-12

CVE-2026-6689: 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…

Priority P4 24 medium 4.3 CVSS 3.1

AV N AC L PR L UI N S U C N I L A N

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

Affected

7 ranges

Vendor	Product	Version range	Fixed in
github.com	mattermost_mattermost-server	>= 10.11.0 < 10.11.17	10.11.17
github.com	mattermost_mattermost-server	>= 11.5.0 < 11.5.5	11.5.5
github.com	mattermost_mattermost-server	>= 11.6.0 < 11.6.1	11.6.1
github.com	mattermost_mattermost_server_v8	>= 8.0.0-20250731163400-5b955468ea1e < 8.0.0-20260501144115-7d6816abdfd1	8.0.0-20260501144115-7d6816abdfd1
mattermost	mattermost	10.11.0 – 10.11.15	—
mattermost	mattermost	11.5.0 – 11.5.4	—
mattermost	mattermost	11.6.0 – 11.6.1	—

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CWE-862