Team admin can escalate a team member's permissions via the team member roles endpoint
Impact
Mattermost versions 11.7.x <= 11.7.10 fail to restrict which built-in roles can be assigned to a team member via the API, which allows a team admin to grant a team member permissions beyond those permitted by the configured permission scheme via the {{update-team-member-roles}} REST API.. Mattermost Advisory ID: MMSA-2026-00734
Source excerpt · MattermostWhat to do
Update Mattermost to versions 11.11.0, 11.7.11 or higher.
Affected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
Mattermost · Mattermost
Other versions: unaffected
| Version / range | Source status |
|---|---|
| 11.7.0 through 11.7.10 (inclusive) | affected |
| 11.11.0 | unaffected |
| 11.7.11 | unaffected |
Original source description
Mattermost versions 11.7.x <= 11.7.10 fail to restrict which built-in roles can be assigned to a team member via the API, which allows a team admin to grant a team member permissions beyond those permitted by the configured permission scheme via the {{update-team-member-roles}} REST API.. Mattermost Advisory ID: MMSA-2026-00734