CVE-2021-39223: Nextcloud Richdocuments

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

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Richdocuments application prior to versions 3.8.6 and 4.2.3 returned verbatim exception messages to the user. This could result in a full path disclosure on shared files. (e.g. an attacker could see that the file `shared.txt` is located within `/files/$username/Myfolder/Mysubfolder/shared.txt`). It is recommended that the Richdocuments application is upgraded to 3.8.6 or 4.2.3. As a workaround, disable the Richdocuments application in the app settings.

Affected products

• Nextcloud Richdocuments: before 3.8.6 (fixed in 3.8.6); from 4.0.0, before 4.2.3 (fixed in 4.2.3)

Published 2021-10-25. Last modified 2026-06-17.