CVE-2026-18256 (GCVE-0-2026-18256)
Vulnerability from cvelistv5
Published
2026-10-16 07:13
Modified
2026-10-16 11:58
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 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to properly restrict private teams from public team search results, which allows an authenticated user without permission to list private teams to disclose the ID, name, and display name of private teams via a modified team search request. Mattermost Advisory ID: MMSA-2026-00748
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.10.0   ≤ 11.10.0
Version: 11.7.0   ≤ 11.7.9
Version: 11.9.0   ≤ 11.9.1
Version: 11.8.0   ≤ 11.8.5
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