Making a cross-domain request in ember.js using an adapter

I am trying to access a third party API via the OAUTH protocol in an application using Ember on my front end and rails on my back end. As it stands, I am able to begin the request phase on my server, but my client is unable to redirect to the authorization page, sending an error reading:

Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access. The response had HTTP status code 404.

The problem here is that the Origin of the request being returned from coinbase is null, so my client rejects it. I need to find some way to bypass this or handle this error. It is worth noting that I am doing my testing on chrome, with my client and server at two different localhost ports. I also have cors configured on my back end and the request is firing with no issue. How can I go about resolving this error in ember?