As a long time user of the avast! Free product and as a lecturer on computer security, this points out that it can happen to any one. The only true defense, is a good offense. If you don't have a good backup strategy, you can pretty much kiss your personal information good bye.
I'm also sure that Avast has the forum backed up and will transfer the information to a more secure platform. By now, I've gotten the "change your password" routine down to a science.
I guess most of us have after the recent Heartbleed fiasco.
Stay safe, be free!