Description
Mattermost versions 11.7.x <= 11.7.10 fail to restrict which built-in roles can be assigned to a team member via the API, which allows a team admin to grant a team member permissions beyond those permitted by the configured permission scheme via the {{update-team-member-roles}} REST API.. Mattermost Advisory ID: MMSA-2026-00734
References1
Metrics
- CVSS 3.1
-
3.8
LOW
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 4 · as of 8 November 2026
- CWE
- CWE-863
Could this be exploited in your environment?
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