Can't filter undisclosed-recipients

[KenJackson]

I get a noticeable amount of spam delivered to an info email address like this:

To: undisclosed-recipients:;

I decided that even if I get legitimate email sent out that way, I don't mind loosing it. So I added an filter to discard messages that match this rule (I've tried other variants also):

To contains undisclosed-recipients

But I still get the spam. Other filters work great. Go ahead users at yahoo.ca and yahoo.fr, send me all the spam you want because I never see it. But this one doesn't work.

Any ideas how to make it work?

[felgall]

That would be your email program adding that text when the To: field is empty. The email doesn't actually contain that text itself..

[KenJackson]

That would be your email program adding that text when the To: field is empty. The email doesn't actually contain that text itself..
I doubt it. The text is actually in the email's header. I guess it could have been added, but to what end? Those words mislead, whereas an empty "To:" field would convey more accurately that no recipient was specified.

Besides, here is an article (http://en.allexperts.com/q/Microsoft-Outlook-1541/Undisclosed-Recipients.htm) in which someone is explaining how to send email to "Undisclosed Recipients" using Microsoft Outlook. I think Microsofties see this as the correct thing to do when you are sending email to a bunch of BCC addresses.

[KenJackson]

I think I have found a solution.

I believe the previous filter doesn't work because the filter software first strips out the human-readable part of the address, and any other junk, leaving only the actual address to be applied to the filter. This seems to be the case based on my experiments. Therefore, 'undisclosed-recipeints' is removed before that filter is applied.

Therefore the filter is now setup to discard email who's To: address does not contain '@'.

[Early Out]

I'd be very careful about dumping messages that are addressed that way. It's standard practice to use the BCC field to address a message when you don't want all the recipients to see all the other addresses. I get legitimate emails that look like that with some regularity.

[KenJackson]

Yes, I do too. That's good advice for personal email addresses.

But this email address is an information address that has gained fairly wide exposure. If the email sent to it is not an individual asking or requesting something specific to the organization, it's junk.

[Early Out]

Yes, in that case, dump the suckers! :)