For GOS 4.2 a new patch level is available:
http://www.greenbone.net/en/roadmap-lifecycle/
This update addresses a single issue in the scanner. This issue caused the scanner
to hang (and time-out) during a scan due to a internal dead-lock situation. In the past
this happened very rarely and it was not reproducable. But recently added NVTs
triggered this more often and we were able to identify and fix this condition.
In total the patch level covers 1 improvement.