PT-2020-8454 · Mattermost · Mattermost Server

Published 2020-06-19 · Updated 2026-03-03 · CVE-2017-18908

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 4.0.0 Mattermost Server version 3.10.2 Mattermost Server version 3.9.2

Description: An issue was discovered where a password-reset request could be sent to an attacker-provided e-mail address.

Recommendations: For Mattermost Server versions prior to 4.0.0, update to version 4.0.0 or later. For Mattermost Server version 3.10.2, update to version 3.10.3 or later, or apply the necessary patch. For Mattermost Server version 3.9.2, update to version 3.9.3 or later, or apply the necessary patch. As a temporary workaround, consider restricting access to the password reset functionality until a patch is available.

Fix

Improper Authentication

Weakness Enumeration

CWE-287

CWE-640

Related Identifiers

CVE-2017-18908

GHSA-34CX-HVM4-VX7J

GO-2026-4476

SUSE-SU-2026:0757-1

Affected Products

Mattermost Server

References · 118

• https://nvd.nist.gov/vuln/detail/CVE-2017-18908 · Security Note
• https://osv.dev/vulnerability/GHSA-34cx-hvm4-vx7j · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:0757-1 · Vendor Advisory
• https://mattermost.com/security-updates · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2017-18908 · Vendor Advisory
• https://osv.dev/vulnerability/GO-2026-4476 · Vendor Advisory
• https://github.com/mattermost/mattermost · Note
• https://github.com/mattermost/mattermost/commit/e5065cf7575ee05c040945a4b00b7fd90bf39b83 · Note
• https://github.com/mattermost/mattermost/commit/59139390ae927af2e879dbacfe4dadb1adac97c0 · Note
• https://github.com/mattermost/mattermost/commit/d3bc11be3acd3a73e6358d958b91427e2584ea71 · 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