There are 2 Master Key vulnerabilities. They can be fixed as follows :
1. Installing a custom ROM Cyanogenmod => http://get.cm (check availability for your phone => http://wiki.cyanogenmod.org/w/Devices#vendor=;)
2. Install the app ReKey => https://play.google.com/store/apps/deta ... ekey.rekey
Check if your phone is patched => https://play.google.com/store/apps/deta ... ootscanner
Tl;dr
=> http://www.saurik.com/id/17