[Mimedefang] Problem with backscatter

Jakub Wasielewski jakub at wasielewski.info
Tue Mar 23 16:27:40 EDT 2010

2010/3/23 - <kd6lvw at yahoo.com>:
>> > Here's your problem.  You haven't checked the sender
>> against SPF....
>> True unless sender is a spamtrap of some dnsbl list - than you're
>> listed and problem is yours ;)
> All proper spamtrap mailboxes should have SPF records indicating that they don't send mail at all ("v=spf1 -all" if the entire domain is a trap), or have a proper record restricting to authorized senders.  In the latter category, a true spamtrap mailbox will NEVER be used as a sender from an authorized place, so it should always fail SPF.
> An UNPROTECTED (by SPF or alternative method; e.g. Domainkeys "always signed") spamtrap mailbox is not a valid construct, but misbehavior as damaging as spam itself.  A spammer may use it as a sending source where the recipient has no way to determine it's not valid (since it's unprotected), and thus any reply (whether manual or automatic) is APPROPRIATE traffic, thus leading to false positive listings.
> The admin. of the backscatterer and UCEprotect lists, is completely CLUELESS as to this requirement.  Every mailbox and domain owner, and especially DNSBL operators, have a responsibility to prevent their mailbox resources from being used as forged sources.  Failure to prevent this pollutes their blacklists.

Yeah, don't tell me about it. My backup MX I'm writing about in this
thread is listed in both of them.
That is really sad that their are so popular and making money for
delisting (UCEprotect)...

I fully agree with what you said, but life is brutal and full od spamtraps ;-)


    Jakub Wasielewski

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