CVE-2017-18899: Mattermost Server

Medium severity, CVSS 5.3. EPSS: 1.1% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. It mishandles IP-based rate limiting.

Affected products

  • Mattermost Mattermost Server: before 4.0.5 (fixed in 4.0.5); from 4.1.0, before 4.1.1 (fixed in 4.1.1); version 4.2.0 only

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