CVE-2026-6689

MEDIUM EPSS 4.8%
Published Jun 12, 20262w ago · Modified Jun 18, 20261w ago
4.3 CVSS 3.1
Medium
Find Similar
Published Jun 12, 2026 2w ago
Last Modified Jun 18, 2026 1w ago

Description

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 Details

Base Score
4.3
Exploitability
2.8
Impact
1.4
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
4.8% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-862 Missing Authorization Authorization

Affected Products 3

VendorProductVersionRange
mattermostmattermost_server*≥10.11.0  –  <10.11.17
mattermostmattermost_server*≥11.5.0  –  <11.5.5
mattermostmattermost_server*≥11.6.0  –  <11.6.2

References 1

  • mattermost.com https://mattermost.com/security-updates
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.