Ars Ex Machina Coda

From Skypher

Ars Ex Machina Coda is a tool to create ASCII Art shellcode - that is working shellcode that looks like ASCII Art. It works similar to ALPHA3 in that it creates a small decoder followed by encoded shellcode data. However, it stores the decoder and shellcode in the ASCII Art, modifying both to make the impact on the appearance of the ASCII Art minimal.

Decoder

The decoder for AEMC only uses printable characters and comes with information about where instructions start and end as well as where (offset) pointers are stored and where they point. This information is used by AEMC to inject extra NOP instructions into the decoder so the decoder can be inserted into the ASCII Art without modifying some chracters that are important to the appearance, such as spaces and CR/LF.

Shellcode

AEMC has a list of which characters are decode by the decoder and which are ignored. It only encodes data into characters in the original ASCII Art that can be replaced without affecting the appearance too much.

Example

An example of an ASCII Art shellcode created using a recent build can be found here.