I've got a problem with SORBS (http://www.dnsbl.nl.sorbs.net) and the FileZilla Server software.
I've got the newest version of FileZilla and configured it to Port 21, Passive Modus is random from port 5000 to 5100.
My hardware firewall allow only mail (25) and ftp (21). I can normally connect, transfer etc. All normal BUT the software allows a connection on port 20!? I don't know why, but the port will be not blocked by our firewall (soft & hardware). So i started a little search on the net and found out, that port 20 is for the data stream. And now the problem: If the SORBS bot see your server, he means, that you are running a ftp server on port 20 (because he sends 220!)...but actually it's the data port.
The exact message in SORBS:
Additional information on the host is: Suspect host (High port FTP server - Hacked?) Port: 20
Any explanations??
(sorry for my bad english - speak better german or swiss-german
)