Shellshock, the newly discovered vulnerability that allows attackers to inject code into your machine, puts your Mac or Linux at a serious risk for malicious attacks. Here's how to test if your machine is vulnerable.


Shellshock uses a bash script to access your computer. From there, they can launch programs, enable features, and access files. The script only affects UNIX-based systems, so Linux and Mac are the only ones vulnerable.


You can test your system by running this test command from Terminal:

env x='() { :;}; echo vulnerable' bash -c 'echo hello'

If you're not vulnerable, you'll get this result:

bash: warning: x: ignoring function definition attempt bash: error importing function definition for `x' hello

If you are vulnerable, you'll get:

vulnerable hello

You can also check the version of bash you're running by entering:

bash --version

If you get version 3.2.51(1)-release as a result, you'll need to update. Many Linux distributions already have patches available, so you can follow these instructions to update your system. Update: Mac users now have patch available from Apple. You can download and install it here.