#fail
That was not a web wallet, it is a screen shot of the native UI that Monero developed in 2014 (can be downloaded and compiled and it does work but back end functions are stubbed out). Work to integrate it with the rest of the code was put on hold for a while to focus on other priorities and is ongoing now.
Like what ? FluffyPony making a gambling website that was hacked ?
Of course patching your own is top priority.
Custom API, so I don't think this affects anyone else. We've disabled betting in the meantime whilst we sort this out, but I really think the lesson to other operators is not to be overconfident in your code or in your setup. Everything can and will be compromised, so assume it's going to happen and put safeguards in place to handle that eventual scenario.