[Mimedefang] .eml attachments

[local.mimedefang]

One of our users is getting a lot of these
(all from the same sender)

>Here are the headers for quarantined part 1:
>Content-type: application/octet-stream; 
>	name="att1.eml"
>Content-Disposition: attachment; filename="att1.eml"
>Content-transfer-encoding: base64
>
>----------
>Here are the warning details:
>
>A non-multipart attachment named att1.eml was removed from this document as
it
>constituted a security hazard.  If you require this document, please
contact
>the sender and arrange an alternate means of receiving it.

I don't know in what way these are dangerous, but I'm sure they are
not sent with any malevolent intent. How risky is it to chop the code
from mimedefang-filter which detects them?