Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to receive write/read privileges on any Federated File Share. Since public links can be added as federated file share, this can also be exploited on any public link. Users can upgrade to patched versions (19.0.11, 20.0.10 or 21.0.2) or, as a workaround, disable federated file sharing.
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
| Link | Tags |
|---|---|
| https://github.com/nextcloud/security-advisories/security/advisories/GHSA-jf9h-v24c-22g5 | third party advisory |
| https://hackerone.com/reports/1170024 | third party advisory permissions required |
| https://security.gentoo.org/glsa/202208-17 | third party advisory vendor advisory |