Perl doesn't work that way. You first declare %cookie as a hash. Then you look for the pass entry of the hash. It's not there because %cookie is empty: you just declared it and Perl doesn't automagically put cookie values in hashes for you.

Since you're using CGI.pm, you might have better luck with:

This will actually retrive the cookie with the name pass from the query, if it exists.

I thought I was reading the cookie while I was checking for pass.

I don't see where you assign to %cookie anywhere before you check it for pass.