Check your Bash version $ bash --version GNU bash, version 3.2.51(1)-release (x86_64-apple-darwin13) Copyright (C) 2007 Free Software Foundation, Inc. Run this following commend on your terminal to find whether your system is vulnerable env x='() { :;}; echo vulnerable' bash -c "echo this is a test" If your system infected by Shellshock you will see the following result. vulnerable this is a test What is the good result? You don't want worry about Shellshock bug if you see the bellow result in your system bash: warning: x: ignoring function definition attempt bash: error importing function definition for `x' this is a test For Fedora, RHEL, CentOS $yum update bash -y To fix bash on your mac Update brew $brew update Install bash with $brew install bash Now add /usr/local/bin/bash to /etc/shells I have tested this on my Mac and updated to bash 4.3.25. seems I am safe. :)