A while ago, I took the wife's old laptop that had been running Windows XP and installed Linux Mint. I thought it was a great move at the time, and I still do. One of the up sides to Linux is that you have less to worry about in the way of virus, etc. But, that doesn't mean it is invulnerable. Just like OSX is not invulnerable.
If you made a similar switch to me or you're running OSX, then you need to check to see if your system has what is being called the Shellshock vulnerability. Let me make one thing clear: there is no need to panic over this. The world isn't ending. And for most, the test is easy and the fix is simple.
PCWorld has all the information on how to check for the vulnerability.
Sure enough, my Linux box which I hadn't used in a couple of days was vulnerable. Fortunately, the patch had already been released. To install it, all I had to do in the terminal was:
sudo apt-get update
sudo apt-get upgrade
And with that, the vulnerability appears to have been resolved based upon the PCWorld test.
So, if you've got a machine that could be subject to this type of vulnerability, check it out and get it fixed. But, please, please, please, whatever you do, take the advice on the cover of the Hitchhiker's Guide to the Galaxy.