in reply to Getting username and password from the URL.

You can set up a simple CGI to show you all the environmental variables. Then just call it and see if there is one that contains the password: 
#!/usr/bin/perl -w

print "Content-type: text/html\n\n<html><body>";
foreach (keys %ENV){
  print "$_ -> $ENV{$_}<br>\n";
}
print "</body></html>";

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