Auth bypass in Mattermost
CVE-2026-6541
Mattermost versions 11.7.x <= 11.7.1, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to restrict metric configuration changes to the playbook being saved, which allows an authenticated user with team access to alter another user’s playbook met…
Vulnerability class: IDOR (Insecure Direct Object Reference)
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.
Affected products
- Mattermost — versions 11.7.0, 11.6.0, 10.11.0
- Mattermost Mattermost_server
Weakness classification (CWE)
References
- responsibledisclosure@mattermost.com (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-6541?
- CVE-2026-6541 is a medium-severity vulnerability in Mattermost, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-07-13.
- How severe is CVE-2026-6541?
- Medium severity. CVSS v3 base score is 4.3 out of 10.