RDNS_NONE false negative

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RDNS_NONE false negative

Postby ics » Wed Jul 08, 2015 12:54 pm

Hi,

I enabled the RDNS_NONE check in MC and I see some spam failing the FCrDNS test and not being tagged.

For example, a spam coming from the IP 182.239.78.148 has been correctly tagged
but not a spam coming from the IP 14.163.248.7.

Both IPs fails the FCrDNS test (http://multirbl.valli.org/fcrdns-test/) but differently.
This one can be reverse resolved but the returned FQDN cannot be resolved back to the IP:

Code: Select all

FCrDNS Test
rDNS for IP 182.239.78.148                             182.239.78.148.hk.chinamobile.com          OK
IP Addresses for 182.239.78.148.hk.chinamobile.com     No record found!                           Failed


This one has no DNS record at all:

Code: Select all

FCrDNS Test
rDNS for IP 14.163.248.7   No record found!   Failed


Any idea to force a RDNS_NONE match when the IP has no DNS record at all ?

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