[Mimedefang] filtering Subjects contains HTML code

[Aleksandar Milivojevic]

Gordon Veri wrote:
> Hello,
> 
> We have been using Mimedefang for nearly a year now  at the company I work
> at with great success. We have some spam coming through because of what I
> believe is HTML code or illegal characters in the subject line.  Below is
> a sample from the sendmail log showing the subject line.  Is there anyway
> to get rid of the messages that begin with '=?utf-8'?  Any rule examples
> would be appreciated or a point in the right direction?
> 
> Oct 27 08:08:10 skyextmta mimedefang.pl[27226]:
> MDLOG,i9RE7V75027868,mail_in,4.266,217.239.20.9,<xxxxxxxxx at xxxxxxxxx>,<xxxxxxx at xxxxxxxxxx>,=?utf-8?q?youngish
> ang ruttish?= =?utf-8?q? misses are awaitin?= =?utf-8?q?g you!?=

That's not HTML.  It is a way to encode non-US ASCII characters into 
headers.  The idea is more or less the same as idea behind 
quoted-printable content type.  You will see those in normal 
communication of anybody not speaking English.  Or even English, if 
Subject is to contain ISO 8859-1 chars with codes 160-255, such as 
copyright, pound, multiply, divide, and so on (and let not forget 
Europens that might want to use Euro symbol in emails).  It is not 
limited to Subject header.  It can be part of From, To, or any other 
header.  For example, take a look into message source of email from Jose 
de Jesus Garcia Hernandez from this very mailing list and see how From 
header looks like.  He might have included some actented chars in 
Subject too, even if it was in English, simply because he is used using 
them.

If you live in US, most of your correspondents will use US-ASCII only, 
and such emails will usually be spam.  If you have any oversees 
correspondents, sooner or later you'll end up refusing some of the 
legitimate email.

-- 
Aleksandar Milivojevic <amilivojevic at pbl.ca>    Pollard Banknote Limited
Systems Administrator                           1499 Buffalo Place
Tel: (204) 474-2323 ext 276                     Winnipeg, MB  R3T 1L7