From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: From: matt@proweb.co.uk To: 9fans@cse.psu.edu Subject: [9fans] re: spam filtering fs MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Mon, 1 Sep 2003 16:31:16 -0400 Topicbox-Message-UUID: 28314c12-eacc-11e9-9e20-41e7f4b1d025 in light of recent forged To: & From: the challenge/response method is going to generate twice as much traffic for such a mail. As far as I can tell, without trying it, the example pipeto sends a copy of the message, virus payload and all to whoever the From: headers suggest, obviating the need to infect the plan9 host to spread itself. You also run the risk of ending up sending to an infected host and throwing your email address into another steaming pot. The next generation will snarf text from existing mails with the intention of defeating Bayes type filters.