Successfull attacks depend on being able to craft shellcodes so they can bypass input filter.
Though 0.3.7 is still in beta state, there seems to be a lot of admins which rely on Sniffit for dumping and controlling network flows in their LANs. This could well go back till 0.3.2 with the introduction of logfiles and log params, supposedly. This is a very simple stack based buffer overflow. Usual stuff, static buffers and user input don't go merrily along together. The problem is evident only when loggin mail headers via the -L flag.