CVE-2018-21249: Mattermost Server

Low severity, CVSS 3.7. EPSS: 0.7% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 5.3.0. It mishandles timing.

Affected products

• Mattermost Mattermost Server: before 5.3.0 (fixed in 5.3.0)

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