CVE-2026-21386 (GCVE-0-2026-21386)
Vulnerability from cvelistv5
Published
2026-03-16 14:51
Modified
2026-03-16 18:39
Severity ?
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
Summary
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to use consistent error responses when handling the /mute command which allows an authenticated team member to enumerate private channels they are not authorized to know about via differing error messages for nonexistent versus private channels. Mattermost Advisory ID: MMSA-2026-00588
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.3.0   ≤ 11.3.0
Version: 11.2.0   ≤ 11.2.2
Version: 10.11.0   ≤ 10.11.10
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