Security Advisory

Group admins can create users with IDs of system folders (NC-SA-2019-015)

12th August 2019

Risk level: Low

CVSS v3 Base Score: 8.4 (AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H)

CWE: Improper Input Validation (CWE-20)

HackerOne report: 508493

Description

Improper Input Validation in Nextcloud Server 15.0.7 allows group admins to create users with IDs of system folders.

Affected Software

• Nextcloud Server < 15.0.8 (CVE-2019-15624)
• Nextcloud Server < 14.0.11 (CVE-2019-15624)

Action Taken

The error has been fixed.

Resolution

It is recommended that the Nextcloud Server is upgraded to 15.0.8.

Acknowledgements

The Nextcloud team thanks the following people for their research and responsible disclosure of the above advisory:

• Leon Klingele - Vulnerability discovery and disclosure.

This advisory is licensed CC BY-SA 4.0.