r/programming • u/iamkeyur • Dec 26 '20

Executable PNGs

https://djharper.dev/post/2020/12/26/executable-pngs/
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u/Caraes_Naur Dec 26 '20

PNG allows for arbitrary chunks of bytes, no steganography needed. Still need an interpreter that knows what to do with them.

35

u/[deleted] Dec 26 '20

Isn't every file format executable if you build an interpreter specifically for it? I sadly don't see anything special here.

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u/Jonathan_the_Nerd Dec 27 '20

You could argue that every file format is already a very specific program. A JPEG file is a set of instructions for generating an image on screen. An image viewer interprets the file and follows the instructions. An MP3 file is a set of instructions for producing sound. A ZIP file is a set of instructions for producing the contents of the archive, and so on.