CVE-2021-41239: Nextcloud Server

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

Nextcloud server is a self hosted system designed to provide cloud style services. In affected versions the User Status API did not consider the user enumeration settings by the administrator. This allowed a user to enumerate other users on the instance, even when user listings where disabled. It is recommended that the Nextcloud Server is upgraded to 20.0.14, 21.0.6 or 22.2.1. There are no known workarounds.

Affected products

• Nextcloud Nextcloud Server: before 20.0.14 (fixed in 20.0.14); from 21.0.0, before 21.0.6 (fixed in 21.0.6); version 22.2.0 only

Published 2022-03-08. Last modified 2026-06-17.