CVE-2017-18914: Mattermost Server

Medium severity, CVSS 5.3. EPSS: 0.8% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7. An external link can occur on an error page even if it is not on an allowlist.

Affected products

• Mattermost Mattermost Server: before 3.6.7 (fixed in 3.6.7); from 3.7.0, before 3.7.5 (fixed in 3.7.5); from 3.8.0, before 3.8.2 (fixed in 3.8.2)

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