Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to properly check for permissions when processing commands in the Gitlab plugin which allows normal users to uninstall instances or setup webhook connections via the {{gitlab instance {option}}} or the {{/gitlab webhook {option}}} commands. Mattermost Advisory ID: MMSA-2026-00600

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

No data.

No data.

No data.

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Vendors Products
References
Link Providers
https://mattermost.com/security-updates cve-icon cve-icon
History

Mon, 18 May 2026 09:00:00 +0000

Type Values Removed Values Added
Description Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to properly check for permissions when processing commands in the Gitlab plugin which allows normal users to uninstall instances or setup webhook connections via the {{gitlab instance {option}}} or the {{/gitlab webhook {option}}} commands. Mattermost Advisory ID: MMSA-2026-00600
Title Instance and webhook GitLab plugin commands were able to be run by non-admin users
Weaknesses CWE-862
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}
cve-icon MITRE

Status: PUBLISHED

Assigner: Mattermost

Published:

Updated: 2026-05-18T08:09:57.222Z

Reserved: 2026-02-24T11:13:17.466Z

Link: CVE-2026-3117

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-18T09:16:22.707

Modified: 2026-05-18T09:16:22.707

Link: CVE-2026-3117

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-18T10:30:23Z