SilverStripe 3.0.12 and 3.1.11 stable are now available, and all users of 3.1.10, 3.0.11, or older are strongly advised to upgrade.
This update includes a fix for a high level security issue noted in the SiteTree class. Details of this fix is available at http://www.silverstripe.org/software/download/security-releases/ss-2015-008-sitetree-creation-permission-vulnerability
Release and upgrading notes can be found at http://docs.silverstripe.org/en/changelogs/3.1.11/ and http://docs.silverstripe.org/en/3.0/changelogs/3.0.12/
Download: http://www.silverstripe.org/software/download/
Announcement: https://groups.google.com/forum/#!topic/silverstripe-announce/lyEtvk1tWwk