wa... so fast .. u read chapter 356 liao??
If orochimaru inside kabuto's body, it is not surprising...
Coz, during orochimaru and itachi confrontation, orochimaru lose
his own body's hand together with the ring. And after sasuke and
orochimaru confrontation, there is a part when kabuto notice
orochimaru's hand... so probably, tat is where it comes from
...