CVE-2026-9824 | Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.1… | CVSS 4.3 MEDIUM

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

Metadata

CVE ID: CVE-2026-9824
State: PUBLISHED
Assigner: Mattermost
Reserved: 2026-05-28 11:32 UTC
Published: 2026-07-13 10:47 UTC
Last updated: 2026-07-13 13:10 UTC
Primary CWE: CWE-862
CWE-862: Missing Authorization
Vendor / Product: Mattermost / Mattermost
Sources: cve.org · NVD

Severity & Metrics

4.3 MEDIUM CVSS 3.1

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

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
Mattermost	Mattermost	—	11.7.0 ≤ 11.7.2, 11.6.0 ≤ 11.6.4, 10.11.0 ≤ 10.11.19, 11.8.0 …

Weakness (CWE)

CWE	Source	Description
CWE-862	cna	CWE-862: Missing Authorization

CVSS scores (1)

Score	Severity	Version	Source	Vector
4.3	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

References (1)

MMSA-2026-00676 https://mattermost.com/security-updates