one dot one dot one dot one dot dot dot…. Yes, last week’s release of WordPress MU wasn’t to be the last one. This is. Really.
This is also a security release fixing a bug in the installer that has existed for quite some time. If you can’t update yet, delete the file index-install.php immediately. That file is only used when you install WordPress MU for the first time so it’s not needed afterwards. Don’t ask, “I’m using version x.x.x, do I need to delete this file?” Just do it. Thanks Mad Sprat for reporting the problem.
The index-install.php in 22.214.171.124 is safe, but I’ve added a note at the end of the install recommending the file be removed. The file is not used after installation and it’s always a good idea to clean up unused scripts.
Get WordPress MU 126.96.36.199 on the download page or wait until your Dashboard upgrader finds the new release.
If you’re adventurous, download and replace the following files on your site to upgrade: