Content-Spoofing in "files" app (NC-SA-2017-006)

5th February 2017

Risk level: Low

CVSS v3 Base Score: 3.1 (AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N)

CWE: User Interface (UI) Misrepresentation of Critical Information (CWE-451)

HackerOne report: 179073

Description

The top navigation bar displayed in the files list contained partially user-controllable input leading to a potential misrepresentation of information.

Affected Software

Nextcloud Server < 10.0.2 (CVE-2017-0888)
Nextcloud Server < 9.0.55 (CVE-2017-0888)

Action Taken

The user-controlled content is now not trusted anymore unless the folder structure exists on the file system.

Resolution

It is recommended that all instances are upgraded to Nextcloud 9.0.55 or 10.0.2.

Acknowledgements

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

Ahsan Tahir - Vulnerability discovery and disclosure.

This advisory is licensed CC BY-SA 4.0.

Security Advisory