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CVE-2026-21386

—
CVSS 3.1
4.3 medium
EPSS
<1%p8
Published
()
Modified
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

Vendors
mattermost
Products
mattermost server
Weakness
CWE-203
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
NVD CVE.org GitHub PoCs EPSS (0.2%)

In the news

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