On Thu, 2016-09-29 at 20:28 -0400, Alex wrote: > > Hi all, > > Has anyone given any thought to special rules or methods designed to > catch greymail? That is, mail that perhaps may be opt-in, but > abusive, > like marketing mailing lists or newsletters? > I use metas for this sort of unwanted mail, in combination with my portmanteau rule builder. What I refer to as a 'portmanteau rule' is one with a large list of alternates.
For example, to catch sales junk I use two portmanteau rules: one contains selling terms and phrases I've found in junk mails and the other rule has product and brand names, also harvested from sales spam. Both rules score very low, 0.01 or less, while the 'sales spam' meta rule has a relatively high score and is only triggered if both the portmanteau rules have fired. One benefit of this approach is that it also catches combinations that haven't previously been used by spammers while, because any of these combinations are rare in ham, generates almost no FPs provided you're reasonably careful about what terms and phrases you include in your portmanteau rules. I wrote the portmanteau rule builder to make editing these giant alternate list rules easier: the rule definition file has each alternate regex on a separate line. It is easily portable because its just an awk script embedded in an bash script. Full documentation and code is here: http://www.libelle-systems.com/free/portmanteau/portmanteau.tgz Martin
