STILO is a steganographic tool for binary programs. It has been presented at the International Conference on Information Security and Cryptology (ICISC) 2004. See the publications page for details on the article or download the slides that have been presented at the conference.
Three redundancies in programs are explored to embed information:
- Instruction Selection: many operations can be accomplished through the use of different instructions
- Instruction Scheduling: the order of instructions within a basic block is free as long as dependencies are respected
- Code Layout: the chains of a program can be placed in any order
You can download STILO here