Smallest x86 ELF Hello World

(That I could achieve)

Final size: 142 bytes

Intro

This page is a combination tutorial/documentary about my attempts at creating the smallest x86 ELF binary that would execute saying Hello World on Ubuntu Linux. My first attempts started with C then progressed to x86 assembly and finally to a hexeditor. I ended up compromising and switching to a "Hi World" app instead in order to fit the string data into the elf magic number. The final result is a completely corrupted x86 ELF Binary that still runs.

From start to finish.

Conclusion.

Final size: 142 bytes

helloworld.tar.gz

I am certain that there are ways to get it even smaller. There may also be more things that can be removed from the header to increase size, but I didn't spend the enough time fully researching the ELF header format. Another option might be to use the a.out format instead of ELF may allow you to get even smaller.

Comments, suggestions, and critical criticism accepted: henszey@gmail.com


Home