Sendmail Security Issue

Support for security such as Firewalls and securing linux
Bangdido
Posts: 1
Joined: 2016/03/30 14:02:07

Sendmail Security Issue

Postby Bangdido » 2016/03/30 14:44:26

Sorry, my English is too bad...

i have a Mail Server with Sendmail as MTA, it was as open relay, now it is closed.
but have this problem:

i'm receiving a lot of spam and viruses from randomuser@mydomain.com even if the user do not exist in mydomain.com (this is mine)
if someone connects to the server (by telnet, or whatever) and use a local (existing or nonexistent) account of my domain, and
send mail to valid user there, the mail is accepted and delivery on local account.

any advice on how to avoid that?

Regards