CVE-2026-9571 (GCVE-0-2026-9571)
Vulnerability from cvelistv5
Published
2026-07-13 07:50
Modified
2026-07-15 04:00
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:N
CWE
  • CWE-305 - – Authentication Bypass by Primary Weakness
Summary
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to invalidate OAuth refresh tokens upon user account deactivation, which allows a deactivated user or an attacker in possession of a valid refresh token to obtain new functional access tokens via the OAuth refresh token grant endpoint.. Mattermost Advisory ID: MMSA-2026-00680
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.7.0   ≤ 11.7.2
Version: 11.6.0   ≤ 11.6.4
Version: 10.11.0   ≤ 10.11.19
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