On Tue, 9 Jun 2015, Matus UHLAR - fantomas wrote:
On 09.06.15 11:29, John Hardin wrote:
Two things that I have found very useful at the MTA level are:
(1) Delay sending your SMTP banner a second or two and reject any sender
that starts sending information before that. This is a built-in option in
Sendmail, google "greet_pause".
even 15...
(2) Check the HELO the other guy sends and reject if it's not a FQDN (i.e.
it's not got any periods at all).
or if it's your FQDN, or your IP - they should use their FQDN, not yours.
Agreed. That's one of the other checks I have, but it rarely hits. Then
again, my volume is tiny... :)
--
John Hardin KA7OHZ http://www.impsec.org/~jhardin/
jhar...@impsec.org FALaholic #11174 pgpk -a jhar...@impsec.org
key: 0xB8732E79 -- 2D8C 34F4 6411 F507 136C AF76 D822 E6E6 B873 2E79
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