CVE-2026-6341 MEDIUM

CVE-2026-6341: Incomplete group locking implementation

Vendor Mattermost
Product Mattermost
Weakness CWE-863 · Incorrect authorization
Published May 18, 2026
Last update May 18, 2026
View on NVD All CVEs

CVSS base score

4.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality None
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

What the vulnerability does

01Description

Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to have API-level checks on which groups the user can create issues or attach comments to which allows a user that is member of multiple groups to create issues to a locked group via direct API requests. Mattermost Advisory ID: MMSA-2026-00602

Key dates

02Disclosure timeline

May 18, 2026 CVE published
May 18, 2026 Record updated

Related vulnerabilities

04Related CVE

CVE-2023-35908 Apache Airflow: Access to DAGs without relevant permission CVE-2025-54267 Adobe Commerce | Incorrect Authorization (CWE-863) CVE-2026-33578 OpenClaw < 2026.3.28 - Sender Policy Allowlist Bypass via Policy Downgrade in Google Chat and Zalouser Extensions CVE-2026-40071 pyLoad WebUI JSON permission mismatch lets ADD/DELETE users invoke MODIFY-only actions CVE-2025-13324 Lack of Invalidation of Legacy Remote Cluster Invite Tokens After Confirmation