This is mind boggling. NSO used a compression format's instructions to create logic gates and then from there "a small computer architecture with features such as registers and a full 64-bit adder and comparator which they use to search memory and perform arithmetic operations", all within a single pass of decompression. Combine this with a buffer overflow and you've got your sploit.
"Now I just have to embed a 64-bit computer architecture into my compression algorithm and... boom. We're in."