SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2025-53971

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…

LOW 3.8EPSS 0.20%

Does this matter?

Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
3.8 LOWCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
EPSS
0.20% probability · 10th percentile
CISA KEV
Not listed
Weakness
CWE-863
Affected
mattermost/mattermost server
Source
responsibledisclosure@mattermost.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.