Mattermost versions 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate authorization for team scheme role modifications which allows Team Admins to demote Team Members to Guests via the PUT /api/v4/teams/team-id/members/user-id/schemeRoles API endpoint.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required High

Scope Unchanged

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Mattermost
  • Mattermost

No data.

No data.

References
Link Providers
https://mattermost.com/security-updates cve-icon cve-icon
History

Thu, 21 Aug 2025 12:45:00 +0000

Type Values Removed Values Added
First Time appeared Mattermost
Mattermost mattermost
Vendors & Products Mattermost
Mattermost mattermost

Thu, 21 Aug 2025 07:45:00 +0000

Type Values Removed Values Added
Description Mattermost versions 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate authorization for team scheme role modifications which allows Team Admins to demote Team Members to Guests via the PUT /api/v4/teams/team-id/members/user-id/schemeRoles API endpoint.
Title Channel and Team Membership APIs inadvertently allow loss of Member privileges.
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 3.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N'}
cve-icon MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2025-08-21T07:31:01.870Z

Updated: 2025-08-21T07:31:01.870Z

Reserved: 2025-07-22T07:46:53.204Z

Link: CVE-2025-53971

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-08-21T08:15:30.540

Modified: 2025-08-21T08:15:30.540

Link: CVE-2025-53971

cve-icon Redhat

No data.