Nextcloud Server before 12.0.8 and 13.0.3 suffers from improper checks of dropped permissions for incoming shares allowing a user to still request previews for files it should not have access to.
https://nextcloud.com/security/advisory/?id=nc-sa-2018-002
https://hackerone.com/reports/358339
Source: Mitre, NVD
Published: 2018-07-05
Updated: 2023-02-28
Base Score: 4
Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N
Severity: Medium
Base Score: 4.3
Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N