10th July 2020
Risk level: Low
CVSS v3 Base Score: 4.7 (AV:P/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L)
CWE: Cross-site Scripting (XSS) - Generic (CWE-79)
HackerOne report: 685552
A cross-site scripting error in Nextcloud Desktop client 2.6.4 allowed to present any html (including local links) when responding with invalid data on the login attempt.
The error has been fixed.
It is recommended that the Nextcloud Desktop client is upgraded to 2.6.5.
The Nextcloud team thanks the following people for their research and responsible disclosure of the above advisory: