ietf-smtp
[Top] [All Lists]

2822 To: header (was Re: [ietf-dkim] Mailing lists as 2822-Sender)

2007-12-05 15:22:19

Hector Santos wrote:

in the same vain many SMTP receivers will fill in the missing 822
required fields.

   FROM:  <<-- x821.MailFrom
   To:    <<-- x821.RcptTo

The latter should never be done.  If there's a missing To: header,
an SMTP receiver should synthesize:

     To: undisclosed-recipients;

Otherwise, you risk exposing Bcc: addresses.

(I suppose it's safe for the MDA to add a To: header upon final delivery
to one and only one recipient.)

Regards,

David.

<Prev in Thread] Current Thread [Next in Thread>