CVE-2026-4286lowCWE-863

CVE-2026-4286: low-severity vulnerability in Mattermost

Playbooks Plugin fails to validate team transfers, allowing unauthorized removal of member access via playbook update

Published

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8Vexday Risk Score

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

ssvc Trackcvss 3.1epss 0.1%
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to check if {{team_id}} was being changed when updating playbooks, allowing users with only {{Manage Playbook Configurations}} permission to change a playbook's team, bypassing manage members restriction via PUT api. Mattermost Advisory ID: MMSA-2025-00552
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
Affected products
Mattermost · Mattermost
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