My System get vuln in Shellshock, what should i do ?

[Muhammad Hafiz Izman Bin Ab Rahim]

mhafizizman@ThinkspiratioN:~$ bash --version
GNU bash, version 4.3.0(1)-release (x86_64-unknown-linux-gnu)
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.


mhafizizman@ThinkspiratioN:~$ env x='() { :;}; echo vulnerable' bash -c
"echo this is a test"
vulnerable
this is a test