There are two approaches to this, depending on how important this is and how flexible/extensible/stable you want or need it to be.

The simple way would be to cause the CGI to return the data in some easily-parsible form, like a Storable block, an XML document, or something similar, then parse it on the client side appropriately.

The ideal way would be to implement a SOAP (or other web-services API) service on the server, and write a client for it.