Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when a (reverse) proxy is configured as trusted proxy the server could be tricked into reading a wrong remote address for an attacker, allowing them executing authentication attempts than intended. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.
The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame, making it more susceptible to brute force attacks.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Nextcloud_server | Nextcloud | 23.0.0 (including) | 23.0.12.13 (excluding) |
| Nextcloud_server | Nextcloud | 24.0.0 (including) | 24.0.12.9 (excluding) |
| Nextcloud_server | Nextcloud | 25.0.0 (including) | 25.0.13.4 (excluding) |
| Nextcloud_server | Nextcloud | 26.0.0 (including) | 26.0.9 (excluding) |
| Nextcloud_server | Nextcloud | 27.0.0 (including) | 27.1.4 (excluding) |
Common protection mechanisms include:
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator. [REF-45]