CVE-2021-32728: End-to-end encryption device setup did not verify public key
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.
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is CVE-2021-32728?
CVE-2021-32728 is a vulnerability in the Nextcloud Desktop Client that allows unauthorized access to private keys.
How does CVE-2021-32728 affect Nextcloud Desktop Client?
CVE-2021-32728 affects Nextcloud Desktop Client versions prior to 3.3.0.
What is the severity of CVE-2021-32728?
The severity of CVE-2021-32728 is medium with a CVSS score of 6.5.
How can I fix CVE-2021-32728?
To fix CVE-2021-32728, update Nextcloud Desktop Client to version 3.3.0 or newer.
Where can I find more information about CVE-2021-32728?
You can find more information about CVE-2021-32728 on the Nextcloud security advisory page and the HackerOne report.