PT-2020-8431 · Mattermost · Mattermost Server

Published 2020-06-19 · Updated 2026-01-06 · CVE-2017-18885

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

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

Name of the Vulnerable Software and Affected Versions: Mattermost Server versions prior to 4.3.0 Mattermost Server version 4.2.1 Mattermost Server version 4.1.2

Description: An issue was discovered in Mattermost Server that allows attackers to gain privileges by accessing unintended "API endpoints" on a user's behalf.

Recommendations: For versions prior to 4.3.0, update to version 4.3.0 or later. For version 4.2.1, update to version 4.3.0 or later. For version 4.1.2, update to version 4.3.0 or later. As a temporary workaround, consider restricting access to unintended API endpoints until a patch is available.

Fix

Improper Privilege Management

Weakness Enumeration

CWE-269

Related Identifiers

CVE-2017-18885

GHSA-G78F-6XQ7-RRHQ

GO-2025-4200

SUSE-SU-2026:0037-1

Affected Products

Mattermost Server

References · 85

• https://nvd.nist.gov/vuln/detail/CVE-2017-18885 · Security Note
• https://osv.dev/vulnerability/SUSE-SU-2026:0037-1 · Vendor Advisory
• https://mattermost.com/security-updates · Vendor Advisory
• https://osv.dev/vulnerability/GO-2025-4200 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2017-18885 · Vendor Advisory
• https://suse.com/security/cve/CVE-2017-18889 · Note
• https://suse.com/security/cve/CVE-2025-0426 · Note
• https://suse.com/security/cve/CVE-2025-68938 · Note
• https://github.com/advisories/GHSA-g78f-6xq7-rrhq · Note
• https://suse.com/security/cve/CVE-2017-18886 · Note
• https://suse.com/security/cve/CVE-2025-34430 · Note
• https://suse.com/security/cve/CVE-2025-62190 · Note
• https://suse.com/security/cve/CVE-2024-41260 · Note
• https://suse.com/security/cve/CVE-2025-47913 · Note
• https://suse.com/security/cve/CVE-2017-18888 · Note