CVE-2025-53971 — Channel and Team Membership APIs inadvertently allow loss of Member privileges.

CVE-2025-53971

Channel and Team Membership APIs inadvertently allow loss of Member privileges. PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
Mattermost / Mattermost	affected 10.5.0 through 10.5.8; affected 9.11.0 through 9.11.17; unaffected 10.10.0; unaffected 10.5.9; unaffected 9.11.18

CWE

CWE-863

References

https://mattermost.com/security-updates

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.