I’ve been doing a little research and it looks like the hacker “Yusuf the Turk” has made a run at several phpBB based sites. Do a Google for “hacked by yusuf” and you’ll see what I mean. Also, apparently phpBB has a bad history of being hacked. I can conclude that the hacker most likely used a vulnerability in phpBB to hack AVN.
I suggest anyone else using this software to immediately have it scanned to see if it has any vulnerabilities. (<- last part a shameless plug for me
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