Nextcloud Server is a self hosted personal cloud system. Due to a pre-flighted HEAD request, the link reference provider could be tricked into downloading bigger websites than intended, to find open-graph data. It is recommended that the Nextcloud Server is upgraded to 28.0.10 or 29.0.7 and Nextcloud Enterprise Server is upgraded to 27.1.11.8, 28.0.10 or 29.0.7.

Nextcloud Server is a self hosted personal cloud system. After an admin enables the default-disabled SVG preview provider, a malicious user could upload a manipulated SVG file referencing paths. If the file would exist the preview of the SVG would preview the other file instead. It is recommended that the Nextcloud Server is upgraded to 27.1.10, 28.0.6 or 29.0.1 and Nextcloud Enterprise Server is upgraded to 24.0.12.15, 25.0.13.10, 26.0.13.4, 27.1.10, 28.0.6 or 29.0.1.

Steeltoe is an open source project that provides a collection of libraries that helps users build production-grade cloud-native applications using externalized configuration, service discovery, distributed tracing, application management, and more. When utilizing multiple Eureka server service URLs with basic auth and encountering an issue with fetching the service registry, an error is logged with the Eureka server service URLs but only the first URL is masked. The code in question is `_logger.LogError(e, "FetchRegistry Failed for Eureka service urls: {EurekaServerServiceUrls}", new Uri(ClientConfig.EurekaServerServiceUrls).ToMaskedString());` in the `DiscoveryClient.cs` file which may leak credentials into logs. This issue has been addressed in version 3.2.8 of the Steeltoe.Discovery.Eureka nuget package.

user_oidc app is an OpenID Connect user backend for Nextcloud. An attacker could potentially trick the app into accepting a request that is not signed by the correct server. It is recommended that the Nextcloud user_oidc app is upgraded to 1.3.5, 2.0.0, 3.0.0, 4.0.0 or 5.0.0.

Nextcloud server is a self hosted personal cloud system. Under some circumstance it was possible to bypass the second factor of 2FA after successfully providing the user credentials. It is recommended that the Nextcloud Server is upgraded to 26.0.13, 27.1.8 or 28.0.4 and Nextcloud Enterprise Server is upgraded to 21.0.9.17, 22.2.10.22, 23.0.12.17, 24.0.12.13, 25.0.13.8, 26.0.13, 27.1.8 or 28.0.4.

user_oidc app is an OpenID Connect user backend for Nextcloud. Missing access control on the ID4me endpoint allows an attacker to register an account eventually getting access to data that is available to all registered users. It is recommended that the OpenID Connect user backend is upgraded to 3.0.0 (Nextcloud 20-23), 4.0.0 (Nexcloud 24) or 5.0.0 (Nextcloud 25-28).