Yesterday when I logged in to my blog dashboard I found this update information for WordPress. As you know WordPress released version 3.1.1 on first week of this month and Yesterday WordPress pushed out an update to this version.
This update will fix some of the major security issues on WordPress 3.1.1 including a vulnerability that allowed Contributor-level users to improperly publish posts. I think WordPress facing this issue for a long time now any how; they claiming that they fixed this issue on updated WordPress version 3.1.2.
This update also fixed some other bugs found on WordPress version 3.1.1.You can Download WordPress 3.1.2 from here or update automatically from your Dashboard.