Hi guys,
I have WordPress version 2.3.1 installed, it got hacked and we have been listed as an Attack Site by Google.
I've removed the offending malware but I don't know how to update from 2.3.1 to the latest version. I guess I just have to download everything as a backup, and upload all of the new files?
Cheers.
It's best to do an incremental upgrade 2.3 to 2.5, 2.5 to 2.8.5, 2.8.5 to 3.0.1 to be sure the database gets upgraded properly. Your current theme probably won't work well under 3.0.1, due to lots of changes.
Once you get to 2.8.5, you can use the automatic upgrade from the dashboard.
Deactivate all plugins, switch to the default theme and thensave a copy of your theme from wp-content/themes to your local PC
Older versions available at http://wordpress.org/download/release-archive/
Also see FAQ: My site was hacked « WordPress Codex and How to completely clean your hacked wordpress installation