Re: mail server vulnerability

[Patrick J Kobly <patrick () kobly com>]

If I had to bet, I'd bet that the setup segregated MSA functionality
from MTA functionality...  So outbound clients have to relay using
Submission (on port 587), requiring SMTP AUTH, while 25 is exposed on
the MX to the outside world to accept inbound mail.  So, while you may
not be able to connect to 25 on the server providing MSA functionality
(or from an internal network), equipment on the net needs to be able to
connect to your MX's 25 (and so could telnet to the MX's port 25, which
it sees as exactly the same as a mail server connecting to it).

PK

Atilla Remote Support wrote:
> Yes, that's what I thought too.
>
> However, I had installed Kerio mailserver once and 
> I don't know how it was done, but manual telnet 
> access was not possible and mailserver to 
> mailserver access was.
>
> Anyway, I wondered if it was possible to protect 
> this because Praveen wrote it. Seemed strange to 
> me to, but i'm not an expert so for me it's better 
> to ask first.:)
>
> Regards,
> Richard.
>   

-- 

 

Patrick Kobly, CISSP

 

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