spammer
Click on the red underlined text to get to the source
... of service is illegal in most - if not all - countries (at least
in the US spammers have been successfully sued). However, with
the original sender in the US, the (innocent) relay in Sweden and
...
... the list of receivers back in the US, the legal process of
getting damages from the spammers becomes extremely difficult.
...
... MTAs did implement enough of the rules
described below (especially the Non-Relay rules), we would get the
spammers out in the open, where they could be taken care of. Either
pure legal actions would help, or we can block them technically using
other rules described below (since the Non-Relay rules now make them
...
... SMTP MTAs implemented them from Day 1,
spammers would still find the remaining 1% and use them. Or
spammers would just switch ...
... spammers would still find the remaining 1% and use them. Or
spammers would just switch gear and connect directly to each and
every recipient host ...
... every recipient host; that will be to a higher cost for the
spammer, but is still quite likely.
...
... cache information
injected in DNS servers or spammers running their own DNS with false
information in them, host ...
...
For some events, like "Denied - you're on the spammer's list", 5xx
may be the correct Return Code, since it terminates the session ...
... Return Code, since it terminates the session at
once and we are done with it (assuming that the spammer plays by the
SMTP rules, which he may decide not to do - in fact he can put the
...
... information to make it possible to trace the mail path, despite
spammers use forged host names in HELO statements etc.
...
... host names MUST NOT be case
sensitive. Since <local-part> may be case sensitive it may be natural
to keep that here. However, since <sPAmMeR@domain.example> and
<spammer ...
... sPAmMeR@domain.example> and
<spammer@domain.example> is most probably the same user and since the
string compares are used to refuse his messages, we suggest that
...
... flexibility - regardless of how well we design anti-spam rules today,
spammers will find ways around them and a well designed MTA should be
flexible enough to meet those new threats.
...
... 1123std3, [3],
and are there to assure that mail sent directly from a spammer's host
to a recipient can be traced with enough accuracy; a typical example
...
... host
to a recipient can be traced with enough accuracy; a typical example
is when a spammer uses a dialup account and the ISP needs to have his
...
...
By doing so they take on the full responsibility to trace spammers
that send from inside their organization or they accept to be held
responsible for those spammers ...
... spammers
that send from inside their organization or they accept to be held
responsible for those spammers' activities. It is REQUIRED that the
information provided in their outgoing mail is sufficient for them to
perform any necessary traces ...
...
Although the fight against spammers is important it must never be
done in a way that violates existing email standards. Since spammers ...
... spammers is important it must never be
done in a way that violates existing email standards. Since spammers
often forge "MAIL From:" addresses it is tempting to put general
...
... recipient, i.e. an error message returned to one single individual.
Since spammers have used "MAIL From: <>" to send to many recipients,
it is tempting to either reject such mail completely or to reject all
but the first recipient. However, there are legitimate causes for an
...
... TCP connection ("read()"
frequency) if there are more than one "RCPT To:" and that way slow
down spammers using "MAIL From: <>".
...
... domain (domain.example). In general these kinds of rules are easily
overcome by the spammers changing "MAIL From:" every so often, but
the ability to block a certain user or a certain domain is quite
...
...
As always this can be overcome by spammers really wanting to do so,
but with more strict rules for relaying it becomes harder and harder.
In fact, catching "typos" at the initial (and official) mail relay is
...
...
Both SMTP VRFY and EXPN provide means for a potential spammer to test
whether the addresses on his list are valid ...
... IP network to the list of accepted networks at
mail.home.example. This does open up some minimal risk of spammers
using that host as their Mail Relay: If they use the same ISP ...
... dialup pool and they configure to use mail.home.example at the same
time as our salesman is on his trip, then the spammers will be
authorized to relay their spam through mail.home.example. However,
...
... authorize Mail Relaying, but of course there is much more to it than
that. When that infrastructure and functionality is all in place,
spammers will have a much harder time forging addresses and hiding.
...
... The fight against spammers includes blocking their hosts (which
is described in this memo). However, there is a great risk that
...