Well, fret not. Apple has just released the OS X bash update via separate downloads for Mavericks, Mountain Lion, and Lion. It’s not yet available via Software Update, or the Mac App Store, but there’s no reason why Apple shouldn’t push it to the channel soon. In the meanwhile, if you cannot wait, you can just head over to those download links to get your GNU Bash shell fixed.
Before today, Apple had announced that OS X users are safe, by default, unless they turn on advanced Unix services.
As good security practice, you should fix the GNU Bash vulnerability anyway, whether or not you use OS X’s advanced Unix services.
Via: 9to5Mac