Have you recently found yourself editing a post on your WordPress install only to find yourself facing the following prompt?

The server at Magic requires a username and password.

Well my friend, you’ve been hacked.  Apparently this has something to do with the cross-site scripting (XSS) bug addressed with the WordPress 2.8.2 and 2.8.3 updates.

I’ve uncreatively dubbed this little baddie “The Magic Hack” and there appears to be a simple way to clear it up.  As it stands, the only file that I’ve seen get affected by this is in “wp-includes/vars.php”.  So if your copy of that file looks nothing like the one available over in the WordPress subversion repository, replace yours with a fresh copy, stat.

In fact, it’d probably be a better idea to upgrade your blog to the most recent version of WordPress using the extended upgrade instructions over on the WordPress Codex.  So yeah, do that instead.

Oh, and if you’re still seeing that prompt after updating “wp-includes/vars.php”, let me know and I’ll update the post when I dig up some more info.

Update: Some people are seeing the hack showing up outside of “wp-includes/vars.php”. If you have SSH access to your server, you should be able to pick out the infected files rather quickly by doing a recursive grep from your site’s root directory:

grep -r -l gzinflate .

This will show you just the filenames where the string “gzinflate” is found. If you want to see the code that grep finds — to provide yourself with a little context — just leave the “-l” switch off of the command.

Should you not have SSH access to the server where your copy of WordPress is installed, I suggest writing your host’s support team. Any host worth their salt wouldn’t mind running the command above and giving you the results.

And if you host your WordPress sites in a Windows based server environment — which doesn’t normally allow for commands like grep — do yourself a favor and go get a real host… ;)