{"id":"CVE-2026-6689","aliases":["GHSA-c28q-m4gf-vg4q"],"url":"https://o3.security/vulnerability/CVE-2026-6689","summary":"*Missing* {{invite_user}} *permission check on team creation allows unprivileged users to set open-invite and allowed-domains team settings*","details":"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","published":"2026-06-12T15:51:30.871Z","modified":"2026-09-29T18:26:39.653459561Z","cvss":{"score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"},"epss":{"score":0.00152,"percentile":0.04689,"asOf":"2026-09-01"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"11.6.1"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"11.5.5"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.11.17"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"8.0.0-20260501144115-7d6816abdfd1"}],"fix":{"url":"https://github.com/mattermost/mattermost/pull/36402","label":"mattermost/mattermost#36402"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6689.json"},{"type":"ADVISORY","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-6689"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36402"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36384"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36383"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36375"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36188"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/977c791e5b54bc14fdb96a2b3dacc85da5d8c623"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/7d6816abdfd170169f717aea43c5716a1f9ef6b0"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/479fc42d0ec6da48e76b59608233d90bfc69769d"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/3a96344214b1a84df70d97052d46b6f2b40b0caa"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/2dea05864024b3254fb28c5ed679592e2b7cd672"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v10.11.16"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v11.5.5"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v11.6.2"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v11.7.0"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-29T18:26:39.653459561Z"}}