Security Breach: A zero byte file created in my home directory

["Deboo ^" <knowledgeful@gmail.com>]

I saw today that there's a zero byte file in my hoem dir with the name
"Brendan" created yesterday but I couldn't search whp created it or
what was the command that created it etc from any  log files.

I did not have a firewall yet. I am testing postfix on and off but
don't keep it onlien for more than a few minutes everytime I test. Can
somone have used that to login to my system? How can I search what
command created that file?

I installed aro-firewall and right now it's logging the arp packets
too to the /var/log/messages which is filling it up.

And JUST now as I am posting this, that file is GONE. I did not delete
it. Even with the firewall, someone is in my computer?

What do I need to do?


Regards,
Deboo

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