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Re: is this an attack on my sendmail?

It looks like one of your users (the "ctladdr=" one) is trying to email yourname@company.com. company.com doesn't appear to be online right now, which is why the connection is timing out.

For the SYN_SENT when doing a netstat, it's likely that your mail server is trying to connect to those mail servers, which are either not online or have some firewall rules blocking you - nothing to worry about.

(sending a TCP packet with the SYN flag set is the first step to making a connection, if those servers were online and responding they would reply with a packet with SYN + ACK set, since your server can't get to them the connection is stuck in the SYN_SENT state until it times out)


> hi guys in my maillog I am receiving many strange message on sendmail like 
> that:
> May 10 18:52:50 xserver sendmail[4444]: g4AIRfa02119: 
> to=<yourname@company.com.>, ctladdr=<one of my user mail> (638/45), 
> delay=03:25:09, xdelay=00:00:00, mailer=esmtp, pri=607606, 
> relay=company.com., dsn=4.0.0, stat=Deferred: Connection timed out with 
> company.com.
> and the other strange thing is that when i try to check the 
> conections(netstat -at) there are one strange like that:
> tcp        0      1 myserver:35169           mywebos.com:smtp        SYN_SENT
> when I use netstat -atn looks like that:
> tcp        0      1 myserver:35169       SYN_SENT

Greg Hunt
800-733-3380 x 107

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