The Shellshock is here–>>SHELLSHOCK:CVE-2014-6271   CVE-2014-7169

Then the code for check:

env X="() { :;} ; echo busted" `which bash` -c "echo completed"

env X="() { :;} ; echo busted" /bin/sh -c "echo completed"

Test and Fix:

For Ubuntu:

sudo apt-get update && sudo apt-get install --only-upgrade bash

For CentOS

sudo yum update bash

Test and check it again.