CVE-2026-26230lowCWE-863

CVE-2026-26230: low-severity vulnerability in Mattermost

Team Admin Privilege Escalation to Demote Members to Guest

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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 10.11.x <= 10.11.10 fail to properly validate permission requirements in the team member roles API endpoint which allows team administrators to demote members to guest role. Mattermost Advisory ID: MMSA-2025-00531
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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