{
"id": "GHSA-c28q-m4gf-vg4q",
"aliases": [
"CVE-2026-6689"
],
"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",
"summary": "Mattermost doesn't enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation",
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "11.6.0"
},
{
"fixed": "11.6.1"
}
]
}
],
"package": {
"name": "github.com/mattermost/mattermost-server",
"ecosystem": "Go"
},
"versions": [
"11.6.0"
]
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "11.5.0"
},
{
"fixed": "11.5.5"
}
]
}
],
"package": {
"name": "github.com/mattermost/mattermost-server",
"ecosystem": "Go"
},
"database_specific": {
"last_known_affected_version_range": "<= 11.5.4"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "10.11.0"
},
{
"fixed": "10.11.17"
}
]
}
],
"package": {
"name": "github.com/mattermost/mattermost-server",
"ecosystem": "Go"
},
"database_specific": {
"last_known_affected_version_range": "<= 10.11.15"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "8.0.0-20250731163400-5b955468ea1e"
},
{
"fixed": "8.0.0-20260501144115-7d6816abdfd1"
}
]
}
],
"package": {
"name": "github.com/mattermost/mattermost/server/v8",
"ecosystem": "Go"
}
}
],
"modified": "2026-08-24T21:35:43Z",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"
}
],
"published": "2026-06-12T18:31:59Z",
"references": [
{
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6689",
"type": "ADVISORY"
},
{
"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": "WEB"
},
{
"url": "https://mattermost.com/security-updates",
"type": "WEB"
},
{
"url": "https://github.com/mattermost/mattermost",
"type": "PACKAGE"
}
],
"schema_version": "1.4.0",
"database_specific": {
"cwe_ids": [
"CWE-862"
],
"severity": "MODERATE",
"github_reviewed": true,
"nvd_published_at": "2026-06-12T17:16:27Z",
"github_reviewed_at": "2026-08-24T21:35:43Z"
}
}