Indeed - this is how they do it - this is why it is important to always use the latest version of any software available, as many scripts are vulnerable - of course it may not always be the forum software that is at fault.
I too have been hacked - fortunately I was able to quickly restore from a backup and patch, without too many people noticing...
And no, I was not using the latest version, so have myself to blame to a degree. Of course the issues with any upgrade is the many hacks that one tends to build in.
What people also have to remember is that an author of a piece of software may not reveal a particular security issue, so as not to alarm people - or to put at risk more people than is necessary.
