CVE-2026-9824 - Vulnerability Details - OpenCVE

Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to check the manage_shared_channels permission in the /share-channel autocomplete handler, which allows an authenticated user without that permission to enumerate configured remote cluster connection metadata via slash command autocomplete.. Mattermost Advisory ID: MMSA-2026-00676

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Mattermost	Mattermost

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products
Mattermost	Mattermost

References

Link	Providers
https://mattermost.com/security-updates

History

Mon, 13 Jul 2026 15:00:00 +0000

Type	Values Removed	Values Added
First Time appeared		Mattermost Mattermost mattermost
Vendors & Products		Mattermost Mattermost mattermost

Mon, 13 Jul 2026 14:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 13 Jul 2026 11:00:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to check the manage_shared_channels permission in the /share-channel autocomplete handler, which allows an authenticated user without that permission to enumerate configured remote cluster connection metadata via slash command autocomplete.. Mattermost Advisory ID: MMSA-2026-00676
Title		Remote cluster metadata enumeration via /share-channel autocomplete
Weaknesses		CWE-862
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-07-13T10:47:33.070Z

Updated: 2026-07-13T13:10:35.463Z

Reserved: 2026-05-28T11:32:33.594Z

Link: CVE-2026-9824

Vulnrichment

Updated: 2026-07-13T13:10:32.896Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-07-13T14:37:52Z

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