In simple words: this exploit creates a new folder (/wp-content/1/) in which it puts spamming html files.
You can read more here: New Wordpress 2.3.3 Exploit/Vulnerability - Adds Spam Directory /wp-content/1/ | Smackdown!
You can read more here: New Wordpress 2.3.3 Exploit/Vulnerability - Adds Spam Directory /wp-content/1/ | Smackdown!