... scriptkiddiez and others hammering on port 23 - check this out:
https://github.com/punktniklas/NiKom/tree/master/Extras/Botcheck
Not written by me but it works damn well. Essentially, it's a "gateway" running
on a Linux machine where you are welcomed with a text and required to enter something to proceed to your BBS. Very simple but it kills 100% of the scripts trying bad things on port 23. Invaluable for me who runs my BBS on a genuine Amiga 2000 who's TCP/IP stack survives about 15 minutes without this small piece of software called Botcheck.
--- NiKom v2.5.0
* Origin: Delta City (deltacity.se, Vallentuna, Sweden) (21:2/130.0)