CVE-2026-6689

mediumpriority · track · 0OT risk · elevatedEPSS 0.002 · 4 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.15% (4th) EPSS

CVSS 4.3 · medium

Is it mine?

24 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

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

cvss

Technical severity, 0–10. One row per scoring source.

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · responsibledisclosure@mattermost.comexploitability 2.8 · impact 1.4

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · OSV

v3.14mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-862USCWE-862US

affected products (24)

Products and version ranges known to be affected.

Mattermost Mattermost Server <10.11.17all versionscert_bundDE
Mattermost Mattermost Server <11.5.5all versionscert_bundDE
Mattermost Mattermost Server <11.6.2all versionscert_bundDE
Mattermost Mattermost Server <11.7.0all versionscert_bundDE
Mattermost Mattermost≤ Server <10.11.17cert_bundDE
Mattermost Mattermost≤ Server <11.5.5cert_bundDE
Mattermost Mattermost≤ Server <11.6.2cert_bundDE
Mattermost Mattermost≤ Server <11.7.0cert_bundDE
Mattermost Mattermost≤ 10.11.0 ≤10.11.16enisa_euvdEU
Mattermost Mattermost≤ 10.11.0 ≤10.11.15enisa_euvdEU
Mattermost Mattermost≤ 11.5.0 ≤11.5.4enisa_euvdEU
Mattermost Mattermost≤ 11.6.0 ≤11.6.1enisa_euvdEU
mattermost mattermost server10.11.0 → 10.11.17nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server11.5.0 → 11.5.5nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server11.6.0 → 11.6.2nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Go github.com/mattermost/mattermost-server10.11.0 → 10.11.17osvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server10.11.0+incompatible → 10.11.17+incompatibleosvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server11.5.0 → 11.5.5osvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server11.5.0+incompatible → 11.5.5+incompatibleosvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server11.6.0 → 11.6.1osvUSpkg:golang/github.com/mattermost/mattermost-server

showing 20 of 24

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-1529Mattermost Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2026-05-14csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Mattermost Server ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
GHSA-c28q-m4gf-vg4qMattermost doesn't enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation2026-06-12ghsa · osvUS
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
GO-2026-6283Mattermost doesn't enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation in github.com/mattermost/mattermost-server2026-08-25vendor · osvUS
Mattermost doesn't enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation in github.com/mattermost/mattermost-server

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund nvd NVD CVE.org MITRE

published 2026-06-12modified 2026-06-18

references (3)

External citations — patches, advisories, analysis.

scry

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