I'll give you an example. Where I work, they require the devs to submit time cards, even if the employee is salaried, through an Oracle time managament system. They want to capitalize certain dev time. Ok. Sure, whatever.
Well, they require me to submit my time for the week within two weeks - so I can't be too late. But I'm always late ... because I'm generally doing more important things and I forget.
So I log onto the app and attempt to submit the time, and a big error message pops up saying that I can't submit because it's past the two week deadline.
Bring up the network traffic, and capture the http traffic for a valid submit (I submit a valid week and see what it sends back to the server). I replay the http action with different params for the late week, and all of a sudden I've submitted a late card.
How can I do this? Because the late validation is done on the front end, not the backend.
This is an **Oracle** app.
Accounting freaks out. They call me wondering how I do this. I just claim it must be an app error because I submitted on time...bla bla..
They still haven't figured it out yet.