Nextcloud Server is a self hosted personal cloud system. Under certain conditions the password of a user was stored unencrypted in the session data. The session data is encrypted before being saved in the session storage (Redis or disk), but it would allow a malicious process that gains access to the memory of the PHP process, to get access to the cleartext password of the user. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2.
The product stores sensitive information in cleartext within a resource that might be accessible to another control sphere.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Nextcloud_server | Nextcloud | 28.0.0 (including) | 28.0.12 (excluding) |
| Nextcloud_server | Nextcloud | 29.0.0 (including) | 29.0.9 (excluding) |
| Nextcloud_server | Nextcloud | 30.0.0 (including) | 30.0.2 (excluding) |
Because the information is stored in cleartext (i.e., unencrypted), attackers could potentially read it. Even if the information is encoded in a way that is not human-readable, certain techniques could determine which encoding is being used, then decode the information. When organizations adopt cloud services, it can be easier for attackers to access the data from anywhere on the Internet. In some systems/environments such as cloud, the use of “double encryption” (at both the software and hardware layer) might be required, and the developer might be solely responsible for both layers, instead of shared responsibility with the administrator of the broader system/environment.