HIGHCVSS 7.1
CVE-2026-8821
CVE-2026-8821 updated by NVD
Summary
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel member-management permission during playbook run creation, allowing an authenticated channel member to add an arbitrary user to a restricted channel via the run owner field.. Mattermost Advisory ID: MMSA-2026-00677
References
Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.
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