I believe CFC is Cold Fusion Component file. I don't know much about CFC but to interact with Cold Fusion, you can use HTTP Service, Web Service and Remote Object from Flex. You cannot use Cold Fusion files within Flex.
I understand your use case is to just call few functions in CFC and use it in flex.
My suggestion would be to use remoting and your flex code should look like this:
<mx:RemoteObject id="abc" endpoint="http://localhost:8500/cfusion/flashservices/gateway" destination="com.adobe.MyCFCService" result="" fault=""/>.
Note: endpoint depends upon your web.xml mapping
while your CFC could be:
<cffunction name="hi" access="remote" returntype="string">
inside a file MyCFCService.cfc under package com.adobe inside your CF web root.
Please take a look aat http://livedocs.adobe.com/flex/3/html/help.html?content=data_access_4.html#202412.
Hope this helps.