CVE-2021-32657: Nextcloud Server

Medium severity, CVSS 4.3. EPSS: 1.8% chance of exploitation in the next 30 days.

Nextcloud Server is a Nextcloud package that handles data storage. In versions of Nextcloud Server prior to 10.0.11, 20.0.10, and 21.0.2, a malicious user may be able to break the user administration page. This would disallow administrators to administrate users on the Nextcloud instance. The vulnerability is fixed in versions 19.0.11, 20.0.10, and 21.0.2. As a workaround, administrators can use the OCC command line tool to administrate the Nextcloud users.

Affected products

• Nextcloud Nextcloud Server: before 19.0.11 (fixed in 19.0.11); from 20.0.0, before 20.0.10 (fixed in 20.0.10); from 21.0.0, before 21.0.2 (fixed in 21.0.2)

Published 2021-06-01. Last modified 2026-06-17.