CVE-2026-21386
Published: Mar 16, 2026
Modified: Mar 16, 2026
CVSS v3.1
4.3
Description
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
| Vendor | Product | Versions |
|---|---|---|
Mattermost | Mattermost | affected 11.3.0 - <= 11.3.0affected 11.2.0 - <= 11.2.2affected 10.11.0 - <= 10.11.10unaffected 11.4.0unaffected 11.3.1+2 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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