Not too long ago, there was a security bug found in WordPress 3.0.1, so the awesome development team released a patch right away WordPress 3.0.2. Well, yesterday they announced yet another security update with the release of WordPress 3.0.3. This release fix issues in the XML-RPC remote publishing interface which under certain circumstances allowed Author- and Contributor-level users to improperly edit, publish or delete posts.
This upgrade is for any site that is using or has Remote Publishing enabled.
Note: By default, remote publishing is turned off. But you may have enabled it to use a remote publishing client such as one of the WordPress mobile apps, or your iPhone etc. You can confirm these settings on the “Settings » Writing” screen.
We have upgraded already… Did you?
Thanks WP Development team for keep us secured 
