Two security researchers demonstrated a man-in-the-middle (MITM) attack on an out-of the-box and most updated Samsung handset that allowed them to intercept voice calls by connecting the device to fake cellular base stations. The issue actually resides in the Samsung’s baseband chip, which comes in Samsung handsets, that handles voice calls but is not directly accessible to the end user. The researchers set up a bogus OpenBTS base station that nearby Samsung devices, including the latest Samsung S6 and S6 Edge, think is a legitimate cellular tower.
Source: https://thehackernews.com/2015/11/hacking-samsung-galaxy.html