CVE-2026-3115 (GCVE-0-2026-3115)
Vulnerability from cvelistv5
Published
2026-03-26 16:23
Modified
2026-03-26 17:51
Severity ?
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-863 - Incorrect Authorization
Summary
Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to apply view restrictions when retrieving group member IDs, which allows authenticated guest users to enumerate user IDs outside their allowed visibility scope via the group retrieval endpoint.. Mattermost Advisory ID: MMSA-2026-00594
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.2.0   ≤ 11.2.2
Version: 10.11.0   ≤ 10.11.10
Version: 11.4.0   ≤ 11.4.0
Version: 11.3.0   ≤ 11.3.1
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