Not every part of a file codes for its apparent output. Comments, symbol names, whitespace, color tables... for most file formats, there are countless variations of the bytes on disk which produce outputs which are visually indistinguishable.
The trick is to identify this space in a way that lets you efficiently iterate through it until you find a version which matches the target hash.
Not every part of a file codes for its apparent output. Comments, symbol names, whitespace, color tables... for most file formats, there are countless variations of the bytes on disk which produce outputs which are visually indistinguishable.
The trick is to identify this space in a way that lets you efficiently iterate through it until you find a version which matches the target hash.