Proxmox gateway can send mail when there is not sender ? why ? and how to block .

[atec666]

i want that PMG do not send mail when sender is empty , how can i do that ?

 

[atec666]

and pmg see :
for one days (8 hours) ... and no protection ?
is it possible to prevent that ?

Outgoing Mails	64209
Bounces (99.95%)	64174

 

[Stoiko Ivanov]

i want that PMG do not send mail when sender is empty , how can i do that ?

This is part of a regular e-mail workflow - mails with empty senders are sent by mailservers to inform users of certain conditions
Blocking those would break mailflow.

you can set a higher score for them in SpamAssassin (GUI->configuration->SpamDetector->Options->Backscatter Score) - but keep in mind that an empty sender is not necessarily related to spam

I hope this helps!

 

[atec666]

This is part of a regular e-mail workflow - mails with empty senders are sent by mailservers to inform users of certain conditions
Blocking those would break mailflow.

you can set a higher score for them in SpamAssassin (GUI->configuration->SpamDetector->Options->Backscatter Score) - but keep in mind that an empty sender is not necessarily related to spam

I hope this helps!

after one night of hard analyse ...

smtp traffic is filtered with PMG BUT ...
imaps, pop3s and submission (587) for heavy client (thunderbird outlook) are hosted by haproxy ... which only .. proxy ! ;-) to our internal mailer.
the internal mailer have been the target of the hacker ... and then he can send many mail (spam) with null sender ... and PGM relays all this shit. (now i block IP on this port)

Is it possible to make this protocols filtered/protected by PMG too ?
Do you see a way to avoid that ?

thank you for your brain time ! ;-)

 

[dcsapak]

Is it possible to make this protocols filtered/protected by PMG too ?

no pmg is an smtp filter only

the internal mailer have been the target of the hacker ... and then he can send many mail (spam) with null sender ... and PGM relays all this shit. (now i block IP on this port)

this has not really anything to do with pmg and could happen regardless which filter/relay you use