CVEvulnerability

CVE-2026-21386

4.3 MEDIUM Published 2026-03-16 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-16
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
4.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Weaknesses
CWE-203

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

Affected configurations

• mattermost mattermost server (>= 10.11.0 < 10.11.11) • mattermost mattermost server (>= 11.2.0 < 11.2.3) • mattermost mattermost server (>= 11.3.0 < 11.3.1)

Related

Weakness · CWE (1)

  • CWE-203 Observable Discrepancy weakness

References