CVE-2019-20883: Mattermost Server

Medium severity, CVSS 4.3. EPSS: 0.6% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 5.8.0, when Town Square is set to Read-Only. Users can pin or unpin a post.

Affected products

• Mattermost Mattermost Server: before 5.8.0 (fixed in 5.8.0)

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