Full Disclosure mailing list archives
Re: throwing the book at spam
From: Valdis.Kletnieks () vt edu
Date: Sun, 16 Jul 2006 20:35:04 -0400
On Sun, 16 Jul 2006 11:33:32 BST, lsi said:
These tests are fairly self-explanatory, with the exception of the analyse_received test. This test analyses the significant Received: headerline inside each mail (there are usually several Received: lines, but only one is relevant for our purpose). Any mail with an invalid Received: line is deleted. The tests for validity are as follows: IP_missing IP_obfuscation IP_unreversible by-line_not_present sending_SMTP_server_unresolvable sending_hostname_not_provided
Note that these tests are *very* hard to get right. In particular, they tend to fail spectacularly if you don't allow for the fact that many times, the mail originates inside an RFC1918 private network, so trying to resolve the IP addresses will fail. There's also a lot of other ways this can bork up if at any time a split-view DNS was involved, or there is/was a temporary DNS outage....
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Current thread:
- throwing the book at spam lsi (Jul 16)
- Re: throwing the book at spam Valdis . Kletnieks (Jul 16)
- Re: throwing the book at spam lsi (Jul 24)
- Re: throwing the book at spam Valdis . Kletnieks (Jul 16)