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http://spamlinks.net/prevent-secure-backscatter-fake.htm

I'm pretty careless with my email and I just don't get much spam. When I do, i make it a practice to bounce my emails.

Almost certainly, when you bounce your email you cause some innocent victim to get backscatter spam because the sender is forged. The only safe way to bounce an email is if you can instruct the server to refuse the message when it arrives -- when you are reading it, it is too late.

By the way, the reason you don't get much spam is because most ISPs run spam filters based on blacklists like Spamhaus. They have gotten quite good.

This story was preceded less than a month ago:
https://tech.slashdot.org/article.pl?sid=08/04/08/2258246

I had a bunch of these back then, now they are happening again. Here is some information about the subject.
http://spamlinks.net/prevent-secure-backscatter.htm

You should only get NDRs from your own ISP, as I undestand it. The other mail admins are being fooled by your spoofed return address, and should know better.

Another page you might want to check out is Spam Links' page of DNS blacklists. (Sorry, forgot to include this in my previous post.)

I have been reading on this lately, and found some products to poison spambots. The site itself (http://spamlinks.net/) is very informative, and gives some pretty good tips/techniques for combating spam.

I have been reading on this lately, and found some products to poison spambots. The site itself (http://spamlinks.net/) is very informative, and gives some pretty good tips/techniques for combating spam.

It goes by various names, here's a collection of implementations (I haven't looked at spam tarring in a year or so myself):
http://spamlinks.net/filter-server-tarpit.htm#impl emented

Spamlinks's list of Zombie Blocklists also has other types of block lists on that page (RBLs, Open Proxy blocklists, Known Spammer blocklists, etc.).

Spam lingo for this phenomenon is "backscatter" or "outscatter" (I prefer the last one, as the bounces are not actually sent "back", but to an innocent third party). Spam Links as a link collection to get you up to date at:

http://spamlinks.net/filter-bounce.htm

A nice solution is Bounce Address Tag Validation (BATV), described at:

http://www.ietf.org/internet-drafts/draft-levine-m ass-batv-00.txt

Abstract:

The envelope of Internet mail contains an RFC2821.MailFrom command, which may supply an address to be used as the recipient of transmission and delivery notices about the original message. Existing Internet mail permits unauthorized use of addresses in the MailFrom command, causing notices to be sent to unwitting and unwilling recipients. Bounce Address Tag Validation (BATV) defines an extensible mechanism for validating the MailFrom address. It also defines an initial use of that mechanism which requires no administrative overhead and no global implementation.