[HELP]Attack to port wiht a xploit hacker

[mt2malaka]

Hello, I am used a files 2010 Daroo with a high security in the port in the metin, but however yesterday a hacker used a xploit to close the port of loggin the user(ch1) y have revised the log and in this site don't have a error.
I need protect my server because, I can't put online the server because this hacker close the port.
I have proved to change the port and encript my client wiht a compiler to menester XD, but anything worked.
I need protect my server or this xploit to consig stop this attack.
all help will be reconpensed.