PT-2020-8461 · Mattermost · Mattermost Server

CVE-2017-18915 · Published 2020-06-19 · Updated 2026-03-03

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 3.8.2 Mattermost Server versions prior to 3.7.5 Mattermost Server versions prior to 3.6.7

Description: An issue was discovered in Mattermost Server. After a restart of a server, an attacker might suddenly gain API Endpoint access.

Recommendations: For versions prior to 3.8.2, update to version 3.8.2 or later. For versions prior to 3.7.5, update to version 3.7.5 or later. For versions prior to 3.6.7, update to version 3.6.7 or later.

Fix

Incorrect Default Permissions

RCE

Weakness Enumeration

CWE-276

CWE-807

CWE-20

Related Identifiers

CVE-2017-18915

GHSA-HXXJ-8PHW-74VW

GO-2026-4462

SUSE-SU-2026:0757-1

Affected Products

Mattermost Server

References · 118

• https://osv.dev/vulnerability/CVE-2017-18915 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-hxxj-8phw-74vw · Vendor Advisory
• https://mattermost.com/security-updates · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2017-18915 · Security Note
• https://osv.dev/vulnerability/GO-2026-4462 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:0757-1 · Vendor Advisory
• https://github.com/mattermost/mattermost · Note
• https://github.com/mattermost/mattermost/commit/fb325cc339eb8d8efb60dbadc48fd38897201c6f · Note
• https://github.com/mattermost/mattermost/commit/0968e4079e0aa670254f3fe3a7248d126e3cf877 · Note
• https://github.com/mattermost/mattermost/commit/c7bdce8a6641ed8d361a43b6004a351535c78423 · Note
• https://suse.com/security/cve/CVE-2026-27590 · Note
• https://suse.com/security/cve/CVE-2026-25120 · Note
• https://suse.com/security/cve/CVE-2026-26190 · Note
• https://suse.com/security/cve/CVE-2026-27017 · Note
• https://suse.com/security/cve/CVE-2026-23991 · Note