Bvi in Debian stable couldn't do it as well so as suggested here (and somewhere else on SF) I converted my file into textual hex representation with xxd myFile.bin > myFile.txt, edited it and converted it back with xxd -r myFile.txt > myEditedFile.bin. Octal cat myFile.bin | tr '\NNN' '\NNN' > myEditedFile.bin can be of help as well.