Spam question

[Reindl Harald]

Am 26.08.2012 23:37, schrieb Heinz Diehl:
> On 26.08.2012, Reindl Harald wrote: 
> 
>> all other machines before can write what they like in mail headers
> 
> You can claim to be who you want to while connecting to a mailserver

yes

> but you can't fake the IP from which you are connecting.

not to the one you are connecting

but you can not trust headers before your own MTA

>  It is logged by the mailserver while connecting between two square brackets.

i know this

> The usual format used in Received: headers is
> 
>  name (dns-name [ip-address])

i know this

> "Name" is easy to forge. "Dns-name" is what a reverse lookup on
> ip-adress delivers. "Ip-adress" reflects the IP of the machine which
> connected to the mailserver which generated this Received: header.
> 
>> no, this is not theory, this is how email works and things are
> 
> Ok, so please show me the evidence of your statement

what did you not understand

your MTA get a connection and have the IP of the last machine involved
in mail tzransmission, bit all other received headers before YOOR
machine are nOT trustable because i can write whatever i want
and how many received-headers i want and submit the message
directly to your MTA

you have NO WAY to say if they are forged or not

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