---
id: CVE-2026-6346
title: >-
  Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3
  fail to sanitize sensitive configuration fields before including them in
  support packet generation, which allows a Mattermost System Admin or any party
  with acce…
summary: >-
  Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3
  fail to sanitize sensitive configuration fields before including them in
  support packet generation, which allows a Mattermost System Admin or any party
  with acce…
severity: high
cvss: 8.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N'
cwe:
  - CWE-200
vendor: mattermost
product: mattermost_server
affected:
  - 'mattermost_server >= 10.11.0, < 10.11.14'
  - 'mattermost_server >= 11.4.0, < 11.4.4'
  - 'mattermost_server >= 11.5.0, < 11.5.2'
patched:
  - mattermost_server 11.5.2
published: '2026-05-18'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T20:10:00.190'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-6346'
references:
  - url: 'https://mattermost.com/security-updates'
    label: responsibledisclosure@mattermost.com
tags:
  - nvd
epss: 0.00408
epssPercentile: 0.33444
ingestedAt: '2026-10-14T20:53:12.301Z'
---

## Overview

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, which allows a Mattermost System Admin or any party with access to a support packet to obtain sensitive credentials in plaintext via downloading a support packet from the System Console.. Mattermost Advisory ID: MMSA-2026-00607

## Affected

- `mattermost_server >= 10.11.0, < 10.11.14`
- `mattermost_server >= 11.4.0, < 11.4.4`
- `mattermost_server >= 11.5.0, < 11.5.2`

## Remediation

Upgrade past the affected range:

- `mattermost_server 11.5.2`