http://wordpress.org/development/2009/10/wordpress-2-8-5-hardening-release/
The headline changes in this release are:
- A fix for the Trackback Denial-of-Service attack that is currently being seen.
- Removal of areas within the code where php code in variables was evaluated.
- Switched the file upload functionality to be whitelisted for all users including Admins.
- Retiring of the two importers of Tag data from old plugins.
http://wordpress.org/download/