CVE-2019-20890: Mattermost Server

Medium severity, CVSS 4.3. EPSS: 0.8% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 5.7. It allows a bypass of e-mail address discovery restrictions.

Affected products

• Mattermost Mattermost Server: before 5.7.0 (fixed in 5.7.0)

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