Rootkits are very common in most popular Operating Systems like Windows, Linux, Unix and any variant of those but they are rarely seen in embedded OS's. This is due to the fact that most of the time embedded OS's are closed source, hence internals of the OS are unknown and reverse engineering process is harder than usual. In real life, it's very common that once an attacker takes control of a system he or she needs to maintain access to it so a rootkit is installed. The rootkit seizes control of the entire system running on that hardware by hiding files, processes, network connections, allowing unauthorized users to act as system administrators, etc.This paper demonstrates that a rootkit with those characteristics can be easily created and deployed for a closed source OS like IOS and run unnoticed by system administrators by surviving to most, if not all, of the security measures given by experts on the field. As a proof of this, different ways to infect a target IOS will be shown like runtime patching and image binary patching. To discuss the binary patching technique from a practical point of view, DIK (Da Ios rootKit) which is a set of python[1] scripts that provides a generic rootkit implementation for IOS will be introduced.