[Mimedefang] Two Subject lines in header

Michael Lang michi+mimedefang at relay3.jackal-net.at
Thu Jun 29 11:51:11 EDT 2006

On Thu, 2006-06-29 at 09:04 -0600, Chris Carey wrote:
> I received a spam message today that the subject line was not tagged.
> Investigating the header I found why.
> "Subject" was specified twice. MIMEDefang only modifed the first "Subject" line.
> MIMEDefang modified the *first* subject with "[spam 15 hits]", but the
> second remained unchanged. Mozilla Thunderbird chose to use the second
> unchanged subject line as the one to show. Having "Subject" twice in
> the email headers seems to be a way to get spam to arrive in someones
> inbox without client-side rules catching it..
> So the obvious question - How to have MIMEDefang catch when Subject is
> specified twice (or more) in the header?

so thats why you should never trust your input data.
how to prevent ?

remove existing X-Spam headers
input your X-Spam header (Yes/No/Score...)

filter on these lines ;)

Kind regards
Michael Lang

> --
> Chris Carey
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Michael Lang <michi+mimedefang at relay3.jackal-net.at>

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