Develop a useful program with (1) one intentional buffer overflow. By a useful program, I mean that the program should simulate some real world process or program (e.g. ATM, movie rental, classified system authentication, etc.). You will not be graded on the complexity of the program, but on the exploitability, ingenuity and creativity of the buffer overflow. The following requirements are mandatory:

The buffer overflow vulnerability shall be exploitable to give access to a value or resource that is otherwise protected by the program or operating system (e.g. free money, unauthorized login/capability). Crashing the program, does not count as an exploit.