shinject is a C based shellcode injection program/library currently supporting 32bit and 64bit MACH-O/ELF/PE

git clone https://github.com/Sonic-64/shinject.git
cd shinject
cd shinject
mkdir build && cd build
cmake ..
make

./shinject_main [options]

Options:
-rm <file_name> remove a signature from file

-i <file_name> <shellcode_file> inject a shellcode to file