Version 3.0.3 of WordPress is now available. This is a security update for all previous WordPress versions. The release comes just 1 week after the version 3.0.2 was available for download.
WordPress 3.0.3 fixes issues in the remote publishing interface, which under certain circumstances allowed Author- and Contributor-level users to improperly edit, publish, or delete posts. According to Peter Westwood from WordPress team, these issues only affect sites that have remote publishing enabled.
The feature called “Remote Publishing” is disabled by default. Some users have it enabled to use a remote publishing client such as one of the WordPress mobile apps. You can check these settings on the “Settings → Writing” screen.
Download 3.0.3 or update automatically from your WP “Dashboard → Updates” screen in your site’s admin area.