Data might not be stolen...
...According to reports a custom firmware for the PS3 is in the wild, making slim consoles in to "developers" consoles.
This gives them access to the PSN Developers network as well as the main PSN,
The upside was being able to bypass checks on games and a few other security hurdles.
But they found a bug (or major FUBAR) where creditcard details are not checked to see if the user owns it with simple name/account check (or even if the card number was a valid one e.g. 16x1's would work.)
Letting people with this firmware but anything they liked on the PSN.