CVE-2026-18430: Humhub

High severity, CVSS 7.2. EPSS: 0.5% chance of exploitation in the next 30 days.

HumHub 1.18.4 contains a stored cross-site scripting vulnerability in the comment-deletion notification flow. A Space administrator can delete another user's comment, choose to notify the original author, and place HTML/JavaScript in the deletion reason.

Affected products

• Humhub Humhub: version 1.18.4 only

Published 2026-08-19. Last modified 2026-08-28.