On Friday I mentioned spam coming from a BarkBox affiliate programme. The original email is here. It’s not terribly exciting, it’s rather typical spam of the sort sent by professional spammers. It’s validly DKIM and SPF authenticated, and DMARC-aligned. It includes invisible white-on-white padding text so that it doesn’t look like image-only spam to naive filters (using...
The Problem With Affiliates
If I see BarkBox I think Spam. That’s because, despite their marketing team effort, facebook and banner ad budget, the main place I see them advertised is via spam in my mailbox. It’s not even good spam. There’s quite a lot of it. Most of it looks much the same, other than the spammer randomizing colours. This one looks better than the black on cyan version, or any of the other...
Reading RFCs
We mention RFCs quite a lot, both explicitly (RFC 6376 is the specification for DKIM) and implicitly (the 822.From aka bounce address aka return path). And we have local copies of a bunch of them to make them easy to refer to (SMTP, MIME, Carrier Pigeons …). They use quite a lot of jargon and implicit information and metadata that’s not really explained terribly clearly anywhere...
Minimal DMARC
The intent of DMARC is to cause emails to silently vanish. Ideally deploying DMARC would cause all malicious email that uses your domain in the From address, but which has absolutely nothing to with you to vanish, while still allowing all email you send, including mail that was sent through third parties or forwarded, to be delivered. For some organizations you can get really close to that ideal...
List the world!
We often say that a blacklist has “listed the world” when it shuts down ungracefully. What exactly does that mean, and why does it happen? Blacklists are queried by sending a DNS lookup for an A record, just the same as you’d find the address of a domain for opening a webpage there. The IP address or domain name that’s being queried is encoded in the hostname that’s...
SpamCannibal is dead
The SpamCannibal blacklist – one that didn’t affect your email too much but which would panic users who found it on one of the “check all the blacklists!” websites – has gone away. It was silently abandoned by the operator at some point in the past year and the domain registration has finally expired. It’s been picked up by domain squatters who, as usual, put a...
#GDPR
Twitter has some opinions on #GDPR. — @rianjohnson (Yes, the director of The Last Jedi) Finds deserted island a message in a bottle washes onto the beach *opens bottle* We’ve updated our Privacy Policy — Marques Brownlee (@MKBHD) May 24, 2018 Happy #GDPR day! #gdprjokes pic.twitter.com/2SVisxIuRY — Luke Stevens (@lukestevens) May 24, 2018 just got a GDPR email from a company...
EFAIL PGP / S/MIME "flaw" ?
There’s going to be a lot of hype today about something the security researchers who found it are calling “EFAIL”. Interviews, commemorative T-Shirts, press tours, hype. The technical details are interesting, but the un-hyped end-user advice would probably be “If you’re using a mail client that’s got bugs in it’s MIME handling, and you’ve configured...
Dodgy PDF handling at Gmail
We sent out some W-9s this week. For non-Americans and those lucky enough not to have to deal with IRS paperwork those are tax forms. They’re simple single page forms with the company name, address and tax ID numbers on them. Because this is the 21st Century we don’t fill them in with typewriters and snail mail them out, we fill in a form online at the IRS website which gives us PDFs...
Laposte rejections
Update: The issue seems to have been resolved and Laposte say they’re no longer sending the 519 responses as of April 25th 2018. Laposte.net are having a bad couple of weeks. There’ve been reports from customers of their IMAP service being unusable, with attempts to move or delete messages timing out and expected emails simply not arriving. Several delivery friends have mentioned that...