Security Advisory

New users can read all Nextcloud Deck data from previous user with same username (NC-SA-2021-007)

3rd June 2020

Risk level: Low

CVSS v3 Base Score: 5.1 (AV:N/AC:H/PR:H/UI:R/S:C/C:L/I:L/A:L)

CWE: Insecure Direct Object Reference (IDOR) (CWE-639)

HackerOne report: 882258

Description

A logic error in Nextcloud Deck 1.0.1 allowed new users with a duplicate user identifier to use deck data of a previous deleted user.

Affected Software

• Nextcloud Deck < 1.0.2 (CVE-2020-8297)

Action Taken

The error has been fixed.

Resolution

It is recommended that the Nextcloud Deck is upgraded to 1.0.2.

Acknowledgements

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

• Stefan Niedermann - Niedermann IT-Dienstleistungen (info@niedermann.it) - Vulnerability discovery and disclosure.

This advisory is licensed CC BY-SA 4.0.