Common CMS
Open Source Programs such as WordPress and Joomla are
susceptible to hacks particularly if the versions are out of
date.
Check your version : should be WP v3.3.1
:
Joomla v2.5.x
Common entry points are also contained within free plugins
obtained on the web and uploaded by the owner of the
website.
examples:
/home/xxxxxxx/public_html/ddd.php
/home/xxxxxxx/public_html/wp-content/themes/deep-silent/404.php
/home/xxxxxxx/public_html/wp-content/themes/twentyten/404.php
