CVE-2025-53971lowCWE-863

CVE-2025-53971: low-severity vulnerability in Mattermost

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

Published

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 3.8epss 0.2%
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/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
Affected products
Mattermost · Mattermost
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