We will release a security update for Contao 3.5 and Contao 4.4 on July 12th, 2017. The fixed vulnerability is not critical, still we strongly recommend to update.
Contao version 4.3.10 is available. Among others, the bugfix release fixes a problem with generating the language cache, which caused the back end to be shown in English only.
Contao version 4.3.8 is available. The bugfix release fixes several problems, including the broken redirect to the last page visited upon login as well as the broken drag and drop sorting of the parent view elements in Firefox.