I got this from my host today.
A new worm has been spreading rapidly today that defaces sites running older version of phpBB, and then attempts to spread itself further. There are two solutions to this and all customers running phpBB should take this warning extremely seriously and act on it as a matter of urgency:
Solution 1: Upgrade to phpBB 2.0.11 - http://www.phpbb.com/downloads.php
Solution 2: Use the fix detailed at http://www.phpbb.com/phpBB/viewtopic.php?t=240513
If you are running a version of phpBB earlier than 2.0.11 please ensure that you upgrade or patch your installation. Unpatched installations that are found to have been exploited will be disabled without notice to preserve server integrity.

A new worm has been spreading rapidly today that defaces sites running older version of phpBB, and then attempts to spread itself further. There are two solutions to this and all customers running phpBB should take this warning extremely seriously and act on it as a matter of urgency:
Solution 1: Upgrade to phpBB 2.0.11 - http://www.phpbb.com/downloads.php
Solution 2: Use the fix detailed at http://www.phpbb.com/phpBB/viewtopic.php?t=240513
If you are running a version of phpBB earlier than 2.0.11 please ensure that you upgrade or patch your installation. Unpatched installations that are found to have been exploited will be disabled without notice to preserve server integrity.