Update the WordPress Core to 3.9.2
If you haven’t already, please upgrade your WordPress core to version 3.9.2. This release contains an important fix for a possible denial-of-service vulnerability in PHP’s XML processing. You can find out more about the fix on the official WordPress blog.
Gmedia Gallery Plugin Vulnerability
The WordPress Gmedia Gallery plugin version 1.2.1 contains a serious shell upload vulnerability which was publicly disclosed on August 2nd and the vendor released a fix the same day.
What to do: If you are using the Gmedia Gallery WordPress plugin, upgrade to the newest release immediately.