WordPress security alert, folks!
From the WordPress blog:
Long story short: If you downloaded WordPress 2.1.1 within the past 3-4 days, your files may include a security exploit that was added by a cracker, and you should upgrade all of your files to 2.1.2 immediately.
Longer explanation: This morning we received a note to our security mailing address about unusual and highly exploitable code in WordPress. The issue was investigated, and it appeared that the 2.1.1 download had been modified from its original code. We took the website down immediately to investigate what happened.
It was determined that a cracker had gained user-level access to one of the servers that powers wordpress.org, and had used that access to modify the download file. We have locked down that server for further forensics, but at this time it appears that the 2.1.1 download was the only thing touched by the attack. They modified two files in WP to include code that would allow for remote PHP execution.
This is the kind of thing you pray never happens, but it did and now weâ€™re dealing with it as best we can. Although not all downloads of 2.1.1 were affected, weâ€™re declaring the entire version dangerous and have released a new version 2.1.2 that includes minor updates and entirely verified files. We are also taking lots of measures to ensure something like this canâ€™t happen again, not the least of which is minutely external verification of the download package so weâ€™ll know immediately if something goes wrong for any reason.
:shock: Holy hotcakes, Batman!
I’m not sure what bothers me more … the fact that someone broke in and was successfully able to modify WP distributable code files without being realized for more than a couple days, or the fact that someone broke in and ONLY modified ONE FILE!
All of my upgrades were done at least a week and a half prior to the break in, so I know none of my sites were affected. Still, I’ll be doing full upgrades soon just to be “on the safe side.”
The blog entry goes on to say that if you are a web host or network admin, to block access to the files theme.php and feed.php. It goes on to suggest blocking access to any query strings with “ix=” or “iz=” in them.
I’ve seen entries of someone trying to access theme.php in my server logs quite frequently over the past few months, so that tells me it’s an exploit that’s been out a little while. But I’m also left to wonder: what if this has happened before and WP is just now noticing?
For those interested, detailed information about the exploit is published by Ivan Fratric (the security guy who reported the situation) here.