Server Side Request Forgery (SSRF) attacks happen when an attacker can supply to the server, a whole or part of, a URL that will in turn be queried by the server. This is problematic since the server is considered to be in a privileged network position and can often reach exposed services that aren't readily available to clients due to network filtering. Leveraging such an attack vector, the attacker can have an impact on other services and potentially disclose information or have other nefarious effects on the system.
The /api/dev-console/proxy/internet endpoint on the OpenShift Console allows authenticated users to have the console's pod perform arbitrary and fully controlled HTTP(s) requests. The full response to these requests is returned by the endpoint.
While the name of this endpoint suggests the requests are only bound to the internet, no such checks are in place. An authenticated user can therefore ask the console to perform arbitrary HTTP requests from outside the cluster to a service inside the cluster.
Impact
An authenticated attacker can have the OpenShift Console carry out arbitrary and fully controlled HTTP(s) requests inside/outside the cluster from outside of the cluster. Full responses to the HTTP requests are returned by the endpoint.
With this primitive, an attacker will be able to target cluster services that are not exposed externally.