SilverStripe 3.0.13 stable is now available. Any site running on 3.0.12 or earlier are strongly advised to upgrade to 3.1.12 preferably, or 3.0.13.
This update includes an XSS security fix which was earlier resolved in the recent 3.1.12 release.
Release and upgrading notes can be found at http://docs.silverstripe.org/en/3.0/changelogs/3.0.13/.
Download: http://www.silverstripe.org/software/download/.
Announcement: https://groups.google.com/forum/#!topic/silverstripe-announce/n3QmnxJLxSg