ietf-smtp
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Re: Returning Details about Spam Evaluation when Rejecting Spam

2009-11-26 10:14:26

My opinion:

The support side will say "the more detail to better" to assist users or operators allowing them to be self-reliant to resolve issues (this helps reduce support cost).

The security side will say "Don't give clues to bad guys." In this specific case, you would be allowing them to learn by trial and error to see how to get better scores. For example, ESMTP AUTH, IMV it is bad idea to issue an specific error that says

   530 BAD USERNAME or
   530 BAD PASSWORD

as oppose to just saying

   530 Authentication required

In my view, in your scoring case, too much information.

You can probably decide this based on who you expect to read this. My suggestion is to log it to a file.

--
Sincerely

Hector Santos
http://www.santronics.com



Дилян Палаузов wrote:


Hello,

When an email is evaluated as spam and in turn is rejected during the SMTP dialog, is it reasonable to show in the SMTP response the result of the spam evaluation or not?

E.g. Using SpamAssassin to filter the messages, what response is better and why?

550 5.7.1 Your mail was evaluated as spam.

or

550-5.7.1 Your mail was evaluated as spam (see below for details).
550-5.7.1
550-5.7.1 -0.0 SPF_PASS SPF: sender matches SPF record
550-5.7.1 -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1%
550-5.7.1 [score: 0.0000]
550 5.7.1 1.0 DKIM_VALID DKIM_VALID


Thanks in advance for your opinion,
  Дилян