Folks who study attacks also found it practical to construct binary attack payloads without particular symbols (or with only particular symbols), in that ways o

Folks who study attacks also found it practical to construct binary attack payloads without particular symbols (or with only particular symbols), in that ways of providing such payloads might constrain valid symbols. X86 attack payloads built, amazingly, with only [A-Za-z0-9]: https://en.wikipedia.org/wiki/Alphanumeric_shellcode https://en.wikipedia.org/wiki/Alphanumeric_shellcode I think I saw similar work with analogous but distinct constraints in addition to [A-Za-z0-9].