email spoofing

[Ivan Arteaga]

Hello list,

 

This is not exactly a MS related issue but mta related, anyway I'll post it
here and u guys let me know what to do..

When I telnet port 25 in some sendmail servers (all  I tried) also postfix
and even ms exchange I can send mails with no authentication (using smtp
commands), all the cases internal mails but also can relay to external
accounts. In both cases I can send mails via mail client (outlook, Eudora
etc.) just defining the account and leaving blank the password field, even
if I have to authenticate the users in order to send email.

Had anyone else see this kinda behavior? It is the default normal behavior
or it is a bug? I will appreciate your comments.

 

Regards,

 

--Ivan.

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