With iOS 10.1, Apple patches the executable JPEG and PDF exploit that lets hackers in
Good news, iPhone and iPad lovers - with the newest iOS 10.1 release, Apple has seemingly plugged the hole that allowed hackers to plunder iOS devices by just showing altered JPEG or PDF files. The only thing require from the user used to be viewing such a JPEG or PDF attachment in an email, message, or on a website. After that the hacker was able to run bad code on the device, and gain access to your device.
source: Hacker News