• I have installed the plugin Bad Behavior
  I have installed the plugin "Bad Behavior". "Bad Behavior is a set of PHP scripts which prevents spambots from accessing your site by analyzing their actual HTTP requests and comparing them to profiles from known spambots. It goes far beyond User-Agent and Referer, however. Bad Behavior is available for several PHP-based software packages, and also can be integrated in seconds into any PHP script." Source
  in Public bookmarks with drupal module plugin security spam wordpress wp

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