seeread writes "I discovered how to hack into and secure user accounts of a rising mobile payment start-up. Account info includes credit card details and usage. The company has big name financial backing and an IRL presence, but very few in-house developers, and they don't seem terribly concerned about security. Good samaritan that I am for now, I sent them an e-mail explaining the lapse on their part, but the responses I have received thus far are confused, aloof and unconvinced. So, I am wondering: what is the appropriate next step? Should I do a proof of concept? Should I go to the investors, or should I post about it somewhere? The representatives haven't been too receptive, despite the fact that their brand seems to be at risk, not to mention all of those users' credit cards. I almost feel like it's my responsibility to blow them out of the water if they have made it this far while compromising such trusted data. And although I would love to be in the paper, this hack is just too easy for it to be respectable, though I am sure the FBI could still be interested in all those credit card numbers."