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

INFO

Published Date :

2026-03-16T14:51:43.263Z

Last Modified :

2026-03-16T18:39:14.064Z

Source :

Mattermost
AFFECTED PRODUCTS

The following products are affected by CVE-2026-21386 vulnerability.

Vendors Products
Mattermost
  • Mattermost
  • Mattermost Server
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-21386.

URL Resource
https://mattermost.com/security-updates cve-icon cve-icon
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