If you need to just read the file, then just use CFFILE to read it into a variable and then dump it into the CFMAIL. If you are sure you need to upload , then 1.) upload the file with CFFILE, then 2.) read the file into a variable with CFFILE, and 3.) dump the file contents into a CFMAIL. Then if you need to 4.) delete the file with CFFILE.
But that's a lot of work and is probably not what you really need to do. Think some more.