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.
The product does not validate, or incorrectly validates, a certificate.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Desktop | Nextcloud | * | 3.3.0 (excluding) |
| Nextcloud-desktop | Ubuntu | hirsute | * |
| Nextcloud-desktop | Ubuntu | impish | * |
| Nextcloud-desktop | Ubuntu | kinetic | * |
| Nextcloud-desktop | Ubuntu | trusty | * |
| Nextcloud-desktop | Ubuntu | upstream | * |
| Nextcloud-desktop | Ubuntu | xenial | * |