“What would you do for 25% more sales?” It’s panicked gift-buying season, and I got mail this morning from Boutique Academia, part of their final push before Christmas. They’re hoping for some Christmas sales in the next three days. They do make some lovely jewelry – ask Laura about her necklace some time – so I clicked on their mail. That’s not good. I...
DKIM Canonicalization – or – why Microsoft breaks your mail
One of these things is just like the other Canonicalization is about comparing things to see if they’re the same. Sometimes you want to do a “fuzzy” comparison, to see if two things are interchangeable for your purposes, even if they’re not exactly identical. As a concrete example, these two email addresses: (Steve) steve@wordtothewise.com “Also Steve”...
Global Suppression Lists
Global Suppression List. Pander File. Screamers List. Whatever you call it, it’s the list of email addresses you suppress from every mailing. If you’re an ESP, this is the list of people who you never, ever want to send email to – and I’m talking about ESP-wide global suppression lists here, not the suppression lists maintained per-customer. Global suppression lists are a...
Traffic Light Protocol
If you’re sharing sensitive computer security information it’s important to know how sensitive a document is, and who you can share it with. US-CERT and many other security organizations use Traffic Light Protocol as shorthand for how sensitive the information in a document is. It’s simple and easy to remember with just four colour categories: Red, Amber, Green and White. If...
Spam, campaign statistics and red flag URLs
It’s not often spammers send me their campaign statistics, but on Tuesday one did. The spam came “from” news@udemy.com, used udemy.com in the HELO and message-ids and, sure enough, was advertising udemy.com: Received: from udemy.com (unknown [198.20.115.217]) by ... From: Udemy <news@udemy.com> Subject: The Photoshop Secret - Master Adobe Photoshop like a Pro...
About the Hillary Clinton email server thing…
I was going to say something about the issue with Hillary Clinton using an email server provided by her own staff for some of her email traffic, rather than one provided by her employer, but @LaneWinree already wrote pretty much what I’d have written, just better than I would have done. So, I guarantee this is exactly how the email server thing went down. Whatever internal system the...
Comodo, TLS certificates and business ethics
We run a lot of our own infrastructure at Word to the Wise. Our email and web presence runs on our own hardware, in our own cabinet in our own network space. Partly that’s because we’re all from very technical backgrounds, and can run them in a way that’s better suited to our needs than an off-the-shelf web service. Partly it’s so we can do things like add instrumentation...
Domain transparency
An email I received this morning got me thinking about how your domain name is one of the main ways you identify yourself if you’re sending email. We talk about domain reputation quite a lot – DKIM and SPF let a sender volunteer a domain name as a unique identifier for recipients to use to track reputation, DMARC allows them to tie that domain to the domain visible to the user in the...
Gmail / Apps authentication issues
I’ve seen several reports of unexpected rejections for unauthenticated email to Google over IPv6 today. Unauthenticated mail over IPv6 is a bad idea, but Google usually spam folders it rather than rejecting it. The Gmail status dashboard is reporting an issue “Some messages sent to consumer Gmail accounts are being rejected due to authentication enforcement” so something...
More on ARC
ARC – Authenticated Received Chain – is a way for email forwarders to mitigate the problems caused by users sending mail from domains with DMARC p=reject. It allows a forwarder to record the DKIM authentication as they receive a mail, then “tunnel” that authentication on to the final recipient. If the final recipient trusts the forwarder, then they can also trust the...