Spamcop mail changes

Spamcop is shutting down it’s email service. While anyone could report spam using Spamcop, the system also provided users email addresses behind the Spamcop filters. This shut down should have no major impact on senders. Email addresses in use will still be accepting email, but that mail will simply be forwarded to another address, instead of users being able to access it through POP or IMAP.
The one problem some senders may have is IF they are solely authenticating through SPF and they are publishing a p=reject DMARC statement. This may result in some of the mail being rejected at the forwarding mail server, like AOL, Yahoo and other services respecting DMARC policy statements.
User forwarded mail will be coming from 68.232.142.20 (esa1.spamcop.iphmx.com) and 68.232.142.151 (esa2.spamcop.iphmx.com). If you don’t want to apply DMARC policy to known forwarded mail, those are the IPs to special case.

Related Posts

Who's publishing DMARC?

DMARC is a way for a domain owner to say “If you see this domain in a From: header and it’s not been sent straight from us, please don’t deliver the mail”. If a domain is only used for bulk and transactional mail, it can mitigate a subset of phishing attacks without causing too many problems for legitimate email.
In other cases, it can cause significant problems. Some of those problems impact discussion lists, but others cause problems for ESPs servicing small companies and individuals. ESP customers use their email addresses in the From: field; if they’re a small customer using the email address provided by their ISP, and that ISP publishes a DMARC record with p=reject, a large chunk of the mail they’re sending will bounce. When that happens recipients will stop getting their email, they’ll be removed from the mailing list due to bounces, and there’s some risk of blocks being raised against the sending IP address.
Because of that, it’s good to be able to see what consumer ISPs are doing with DMARC.
I’ve created a tool at dmarc.wordtothewise.com that regularly checks a list of large consumer ISPs and webmail providers and sees what DMARC records they’re publishing.
There are two main variants of DMARC records.
One is policy “reject” – meaning that mail that isn’t authenticated (or for which authentication has been broken in transit) will likely be rejected.
The other is policy “none” – meaning that the ISP publishing the record doesn’t want recipients to change their delivery decisions, but are asking for feedback about their mailstream, and how much of it fails authentication. That can mean that the ISP is evaluating whether or not to publish p=REJECT, or is in the process of deploying p=REJECT. Or it can just mean that they’re using DMARC to monitor where mail using their domain in the From: address is being sent from. There’s no way to tell which is the case unless they’ve made an announcement about their plans.
Hopefully this will be a useful tool to monitor DMARC deployment by consumer ISPs, and to help diagnose delivery problems that may be caused by DMARC.

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Is gmail next?

I’m hearing hints that there are some malware or phishing links being sent out to gmail address books, “from” those gmail addresses. If that is what’s happening then it’s much the same thing as has been happening at Yahoo for a while, and AOL more recently, and that triggered their deployment of DMARC p=reject records.
It’s going to be interesting to see what happens over the next few days.
I’ve not seen any analysis of how the compromises happened at Yahoo and AOL – do they share a server-side (XSS?) security flaw, or is this a client-side compromise that affects many end users, and is just being targeted at freemail providers one at a time?
Does anyone have any technical details that go any deeper than #AOLHacked and #gmailhacked?

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AOL publishes a p=reject DMARC record

Yesterday I mentioned that there were reports of a compromise at AOL. While the details are hazy, what has been reported is that people’s address books were stolen. The reports suggest lots of people are getting mail from AOL addresses that they have received mail from in the past, but that mail is coming from non AOL servers. In an apparent effort to address this, AOL announced today they have published a p=reject DMARC record.
I expect this also means that AOL is now checking and listening to DMARC records on the inbound. During the discussions of who was checking DMARC during the Yahoo discussion, AOL was not one of the ISPs respecting DMARC policy statements. I’m not surprised. As more information started coming out about this compromise, I figured that the folks attacking Yahoo had moved on to AOL and that AOL’s response would be similar to Yahoo’s.
My prediction is that the attackers will be trying to get into Outlook.com and Gmail, and when they do, those ISPs will follow suit in publishing p=reject messages. For those of you wondering what DMARC is about, you can check out my DMARC primer.

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