CVE-2019-20846: Mattermost Server

High severity, CVSS 7.5. EPSS: 1.1% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 5.18.0. It has weak permissions for server-local file storage.

Affected products

• Mattermost Mattermost Server: before 5.18.0 (fixed in 5.18.0)

Published 2020-06-19. Last modified 2026-06-17.