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.
--
Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
One OS to rule them all, One OS to find them,
One OS to bring them all and into darkness bind them
