After a bit of consideration I have removed this from my site. It was not my intention to assist anyone in a hacking a bank site and to be honest I am a bit skeptical that this would be a practical approach. After all without a valid username and password you would need to perform some sort of brute force attack which would certainly be detected and dealt with long before you were able to get in.

Maybe I am missing something. I am not a security expert. If I am able to adequately confirm my belief I will replace the script. In the meantime better safe than sorry.