Thats right geohot the same dev that brought jailbreaks for the iphone back in the day is back with one of the easiest and biggest root exploits in a long time for android.
The video here will show you just how easy it is.
You can get the root app at http://towelroot.com
And make sure to donate to the developer! I cant stress this enough.

Let us know if it works for you

Root ATT Galaxy S5 or any android Towelroot: http://youtu.be/hmp-ETSlV4w