4.3
MEDIUM CVSS 3.1
CVE-2026-9824
Remote cluster metadata enumeration via /share-channel autocomplete
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

INFO

Published Date :

July 13, 2026, 11:16 a.m.

Last Modified :

July 13, 2026, 11:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-9824 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 9302f53e-dde5-4bf3-b2f2-a83f91ac0eee
CVSS 3.1 MEDIUM [email protected]
Solution
Update Mattermost to a version that includes the fix for the shared channel permission check.
  • Update Mattermost to the latest version.
  • Verify shared channel permission checks.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-9824.

URL Resource
https://mattermost.com/security-updates
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-9824 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-9824 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-9824 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-9824 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 13, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Mattermost', 'product': 'Mattermost', 'versions': [{'status': 'affected', 'version': '11.7.0', 'versionType': 'semver', 'lessThanOrEqual': '11.7.2'}, {'status': 'affected', 'version': '11.6.0', 'versionType': 'semver', 'lessThanOrEqual': '11.6.4'}, {'status': 'affected', 'version': '10.11.0', 'versionType': 'semver', 'lessThanOrEqual': '10.11.19'}, {'status': 'unaffected', 'version': '11.8.0'}, {'status': 'unaffected', 'version': '11.7.3'}, {'status': 'unaffected', 'version': '11.6.5'}, {'status': 'unaffected', 'version': '10.11.20'}], 'defaultStatus': 'unaffected'}]
    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
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
    Added CWE CWE-862
    Added Reference https://mattermost.com/security-updates
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.