Vulnerability Description
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Nextcloud | Desktop | < 3.3.0 |
| Debian | Debian Linux | 10.0 |
Related Weaknesses (CWE)
References
- https://github.com/nextcloud/desktop/pull/3338PatchThird Party Advisory
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5ExploitThird Party Advisory
- https://hackerone.com/reports/1189162ExploitThird Party Advisory
- https://www.debian.org/security/2021/dsa-4974Third Party Advisory
- https://github.com/nextcloud/desktop/pull/3338PatchThird Party Advisory
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5ExploitThird Party Advisory
- https://hackerone.com/reports/1189162ExploitThird Party Advisory
- https://www.debian.org/security/2021/dsa-4974Third Party Advisory
FAQ
What is CVE-2021-32728?
CVE-2021-32728 is a vulnerability with a CVSS score of 6.5 (MEDIUM). The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an ...
How severe is CVE-2021-32728?
CVE-2021-32728 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-32728?
Check the references section above for vendor advisories and patch information. Affected products include: Nextcloud Desktop, Debian Debian Linux.