Today I found on my raq's admin mail account a strange error e-mail coming from postoffice@snakefeet.com for postmaster@saintrochtree.com. I don't know snakefeet.com and saintrochtree.com is one of my own domains.
The content is :
#######
The original message was received at 2001-12-27 10:31:34 -0600
from postoffice.208.223.8.75 [10.0.0.1]
----- The following addresses had permanent fatal errors -----
-----Transcript of session follows -----
... while talking to postoffice.208.223.8.75.:
>>> RCPT To:
<<< 550 5.1.1 unknown or illegal alias: yoshi@snakefeet.com
550
#######
and the attached message delivery status is :
#######
Reporting-MTA: dns; postoffice.208.223.8.75
Received-From-MTA: DNS; postoffice.208.223.8.75
Arrival-Date: 2001-12-27 10:31:34 -0600
Final-Recipient: RFC822; yoshi@snakefeet.com
Action: failed
Status: 5.1.1
Remote-MTA: DNS; postoffice.208.223.8.75
Diagnostic-Code: SMTP;550 5.1.1 unknown or illegal alias: yoshi@snakefeet.com
Last-Attempt-Date: 2001-12-27 10:31:34 -0600
#######
My question is about the origin of that mail. Does somebody use my smtp server as an anonymous relay? I felt that raq4 only allows the use of smtp after a pop3 session. I tried it and I've a
relaying denied message for destination domain outside my raq. It's logical.
Another option is that somebody send disguised spam to postmaster@somedomain?
Any idea?
Thank in advance.