Bypassing quota limitation (NC-SA-2017-005)
5th February 2017
Risk level: Low
CVSS v3 Base Score: 0 (AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:N)
CWE: Reliance on Untrusted Inputs in a Security Decision (CWE-807)
HackerOne report: 173622
Description
Due to not properly sanitzing values provided by the `OC-Total-Length` HTTP header an authenticated adversary may be able to exceed their configured user quota. Thus using more space than allowed by the administrator.
Affected Software
- Nextcloud Server < 10.0.2 (CVE-2017-0887)
- Nextcloud Server < 9.0.55 (CVE-2017-0887)
Action Taken
The `OC-Total-Length` HTTP header is now properly sanitized.
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:
- Nordin - Vulnerability discovery and disclosure.
This advisory is licensed CC BY-SA 4.0.