The Five-Ten website has a notice that they have retired the blacklist. Five-Ten wasn’t the greatest list for blocking mail, they aggressively listed senders and there were a number of false positives against a standard mail stream. But it was useful as a touchpoint. If I had a client that wasn’t listed on Five-Ten that told me something about their normal practices.
I updated the Wiki a few weeks ago when I heard, but don’t think I posted anything here. Comcast has changed their delisting form page to http://postmaster.comcast.net/block-removal-request.html. The old form is currently non-functional. You can fill it in, but it’s unconnected to anything on the back end and it won’t result in an IP being delisted from the various Comcast blocklists.
My understanding is that the old form may come back to life at some point, but it’s much safer to use the new form and the new Comcast Postmaster Site.
There is a new type of blocking designed to interrupt the ability of users to click and visit phishing sites.
DNS Response Policy Zones allows companies running recursive resolvers to create a zone that will not resolve specific domains. This is a second layer of filtering, if a spammer manages to get an email with a malicious link into the inbox then the ISP can still protect the user from becoming a victim from the scam. For more detailed information about RPZ, check out the helpful slides published by ISC.
Two blocklists announced this morning that they were publishing lists in RPZ format so ISPs can import the data into their DNS recursive resolver. SURBL is currently offering their list as RPZ. Spamhaus is currently running a beta for the DBL in a RPZ format. If you’re a current DBL user, talk to Spamhaus about checking out their new format.
Recently, an abuse desk rep asked what to do when customers were complaining about being assigned an IP address located on a blocklist. Because not every blocklist actually affects mail delivery it’s helpful to identify if the listing is causing a problem before diving in and trying to resolve the issue.
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