Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 22.0.0 and prior to versions 22.2.10.13, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, missing protection allows an attacker to brute force the client secrets of configured OAuth2 clients. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 22.2.10.13, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 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 | 22.0.0 (including) | 22.2.10.14 (excluding) |
| Nextcloud_server | Nextcloud | 23.0.0 (including) | 23.0.12.9 (excluding) |
| Nextcloud_server | Nextcloud | 24.0.0 (including) | 24.0.12.5 (excluding) |
| Nextcloud_server | Nextcloud | 25.0.0 (including) | 25.0.9 (excluding) |
| Nextcloud_server | Nextcloud | 26.0.0 (including) | 26.0.4 (excluding) |
| Nextcloud_server | Nextcloud | 27.0.0 (including) | 27.0.0 (including) |
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]