Mattermost Server 9.11.x < 9.11.17 / 10.5.x < 10.5.7 / 10.7.x < 10.7.4 / 10.8.x < 10.8.2 (MMSA-2025-00490)

medium Nessus Plugin ID 242670

Synopsis

The remote host is missing a security update.

Description

The version of Mattermost Server installed on the remote host is affected by a vulnerability as referenced in the MMSA-2025-00490 advisory.

- Mattermost versions 10.5.x <= 10.5.6, 10.8.x <= 10.8.1, 10.7.x <= 10.7.3, 9.11.x <= 9.11.16 fail to verify authorization when retrieving cached posts by PendingPostID which allows an authenticated user to read posts in private channels they don't have access to via guessing the PendingPostID of recently created posts. (CVE-2025-6226)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to Mattermost Server version 9.11.17 / 10.5.7 / 10.7.4 / 10.8.2 / 10.9.0 or later.

See Also

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

Plugin Details

Severity: Medium

ID: 242670

File Name: mattermost_server_MMSA-2025-00490.nasl

Version: 1.2

Type: remote

Family: CGI abuses

Published: 7/24/2025

Updated: 7/25/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:N/A:N

CVSS Score Source: CVE-2025-6226

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Vulnerability Information

CPE: cpe:/a:mattermost:mattermost_server

Required KB Items: installed_sw/Mattermost Server

Patch Publication Date: 6/18/2025

Vulnerability Publication Date: 7/18/2025

Reference Information

CVE: CVE-2025-6226

IAVA: 2025-A-0538