CVE-2026-4286 LOW

CVE-2026-4286: Playbooks Plugin fails to validate team transfers, allowing unauthorized removal of member access via playbook update

Vendor Mattermost
Product Mattermost
Weakness CWE-863 · Incorrect authorization
Published May 18, 2026
Last update May 18, 2026
View on NVD All CVEs

CVSS base score

3.1/10
Attack vector Network
Attack complexity High
Privileges required Low
User interaction None
Confidentiality None
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

What the vulnerability does

01Description

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

Key dates

02Disclosure timeline

May 18, 2026 CVE published
May 18, 2026 Record updated