PT-2020-8449 · Mattermost · Mattermost Server

Published 2020-06-19 · Updated 2026-03-03 · CVE-2017-18903

Positive Technologies (AI Summary)

CVSS v3.1

8.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions: Mattermost Server versions prior to 4.0.0 Mattermost Server versions 3.10.2 and earlier Mattermost Server versions 3.9.2 and earlier

Description: An issue allows CSRF to occur if CORS is enabled.

Recommendations: For versions prior to 4.0.0, update to version 4.0.0 or later. For versions 3.10.2 and earlier, update to version 3.10.3 or later. For versions 3.9.2 and earlier, update to version 3.9.3 or later.

Fix

CSRF

Weakness Enumeration

CWE-352

Related Identifiers

CVE-2017-18903

GHSA-FCWG-45JH-5QHF

GO-2026-4305

SUSE-SU-2026:0757-1

Affected Products

Mattermost Server

References · 117

• https://osv.dev/vulnerability/SUSE-SU-2026:0757-1 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-fcwg-45jh-5qhf · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2017-18903 · Security Note
• https://osv.dev/vulnerability/CVE-2017-18903 · Vendor Advisory
• https://mattermost.com/security-updates · Vendor Advisory
• https://osv.dev/vulnerability/GO-2026-4305 · Vendor Advisory
• https://github.com/mattermost/mattermost · Note
• https://github.com/mattermost/mattermost/commit/312269ad0bd166174f07f9df7391fce714601600 · Note
• https://github.com/mattermost/mattermost/commit/a18479df0940be8503c9b88993490741793eba9e · Note
• https://github.com/mattermost/mattermost/commit/4519b03d95e8bfe1b2f74094673ae1a2f39f6b47 · Note
• https://suse.com/security/cve/CVE-2025-64111 · Note
• https://suse.com/security/cve/CVE-2026-0998 · Note
• https://suse.com/security/cve/CVE-2026-24122 · Note
• https://suse.com/security/cve/CVE-2026-22892 · Note
• https://suse.com/security/cve/CVE-2026-21434 · Note