CVE-2021-43847: Humhub

Medium severity, CVSS 6.5. EPSS: 1.2% chance of exploitation in the next 30 days.

HumHub is an open-source social network kit written in PHP. Prior to HumHub version 1.10.3 or 1.9.3, it could be possible for registered users to become unauthorized members of private Spaces. Versions 1.10.3 and 1.9.3 contain a patch for this issue.

Affected products

• Humhub Humhub: before 1.9.3 (fixed in 1.9.3); from 1.10.0, before 1.10.3 (fixed in 1.10.3)

Published 2021-12-20. Last modified 2026-06-17.