SSH Attempts: Link to RedHat?

[Gregg Sperling <gs-list () glsrms com>]

Early yesterday, I received a single connection attempt on three of my 
Linux-based direct connected Internet servers:

Dec 16 01:56:08 srvr001 sshd2[42]: connection from "24.5.243.0"  (ip 
address blocked to protect user)
Dec 16 01:56:09 srvr001 sshd2[6969]: Local disconnected: Connection closed 
by remote host.
Dec 16 01:56:09 srvr001 sshd2[6969]: connection lost: 'Connection closed by 
remote host.'
Dec 16 01:56:40 srvr002 sshd2[41]: connection from "24.5.243.0" (ip address 
blocked to protect user)
Dec 16 01:56:41 srvr002 sshd2[10007]: Local disconnected: Connection closed 
by remote host.
Dec 16 01:56:41 srvr002 sshd2[10007]: connection lost: 'Connection closed 
by remote host.'
Dec 16 02:02:41 srvr003 sshd2[44]: connection from "24.5.243.0" (ip address 
blocked to protect user)
Dec 16 02:02:42 srvr003 sshd2[13440]: Local disconnected: Connection closed 
by remote host.
Dec 16 02:02:42 srvr003 sshd2[13440]: connection lost: 'Connection closed 
by remote host.'

I ran some diagnostic tests on the IP address listed, and found it to be a 
RedHat based Linux system with several ports open,
including HTTP, Telnet, FTP, X11, and "others."

I connected to the website connected to this server, and found somebody's 
personal webpage.  I found their email address, and sent the
owner an email.

Surprisingly, I have had several pleasant exchanges with the individual who 
runs the server.  He has offered to allow me access
into his server with root access.  I'd like to find out what breach, if 
any, caused this connection attempt.

Besides checking the standard /var/log/messages log, are there any 
suggestions as to where I should check for possible breaches
in this individual's system?

Hints?  Suggestions?  Ideas?

Thanks in advance for your time,
Gregg Sperling
gsperling -at- glsrms -dot- com


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