How to solve Ghost in Ubuntu

What is Ghost in Ubuntu?? How to solve?

First check system vulnerability :
#ldd -- version

Output :
ldd (Ubuntu GLIBC 2.19-10ubuntu2) 2.19
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Written by Roland McGrath and Ulrich Drepper.

If versi under 2.17, go update :
#sudo apt-get update
#sudo apt-get dist-upgrade
after that reboot the server.

Source ghost vulnerablity :
http://chargen.matasano.com/chargen/2015/1/27/vulnerability-overview-ghost-cve-2015-0235.html