CVE-2025-53971

LOW

Mattermost 9.11.0-9.11.17 and 10.5.0-10.5.8 - Incorrect Authorization via Team Scheme Role Modification API

Title source: llm

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.

References (1)

Core 1

Core References

Vendor Advisory

https://mattermost.com/security-updates

Scores

CVSS v3 3.8

EPSS 0.0006

EPSS Percentile 18.1%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-863

Status published

Products (4)

mattermost/mattermost 0 - 8.0.0-20250721095846-c602a4a78e1fGo

mattermost/mattermost-server 0 (2 CPE variants)Go

mattermost/mattermost-server 10.5.0 - 10.5.9Go

mattermost/mattermost_server 9.11.0 - 9.11.18

Published Aug 21, 2025

Tracked Since Feb 18, 2026