TWSD: Adapt to filters

This morning the new Yahoo! CEO posted about changes to Yahoo! mail. I logged into one of my Yahoo accounts to check and see if I had access to the new Yahoo! mail client yet. I don’t, but I did notice that spammers have adapted to the new Yahoo model of disabling filters in the mail folder. Most of the mail in my inbox has, at the very top of the message “Click not spam to enable links!”
My favorite has to be the animated gif of how to click “not spam.”
Spammers spend so much time and energy compensating for filters, hopping IP addresses, rotating through domains, and specially creating mail for different ISPs. I have to wonder, though, if they would waste less time by sending opt-in mail.

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Penkava v. Yahoo: wiretapping

According to stipulations filed yesterday Penkava and Yahoo! have agreed to go to private arbitration. This will happen before September 1, 2013. Also filed yesterday was an agreement that Yahoo! has until September 7, 2012 to respond to the complaint.

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Harvesting and forging email addresses

For the contact address on our website, Steve has set up a rotating set of addresses. This is to minimize the amount of spam we have to deal with coming from address harvesters. This has worked quite well. In fact it works so well I didn’t expect that publishing an email address for taking reader questions would generate a lot of spam.
Boy, was I wrong. That address has been on the website less than a month and I’m already getting lots of spam to it. Most of it is business related spam, but there’s a couple things that make me think that someone has been signing that address up to mailing lists.
One is the confirmation email I received from Yelp. I don’t actually believe Yelp harvested my address and tried to create me an email account. I was happy when I got the first mail from Yelp. It said “click here to confirm your account.” Yay! Yelp is actually using confirmations so I just have to ignore the mail and that will all go away.
At least I was happy about it, until I started getting Yelp newsletters to that address.
Yelp gets half a star for attempting to do COI, but loses half for sending newsletters to people who didn’t confirm their account.
I really didn’t believe that people would grab a clearly tagged address off the blog and subscribe it to mailing lists or networking sites. I simply didn’t believe this happened anymore. I know forge subscribing used to be common, but it does appear that someone forge signed me up for a Yelp account. Clearly there are more dumb idiots out there than I thought.
Of course, it’s not just malicious people signing the address up to lists. There are also spammers harvesting directly off the website.
I did expect that there would be some harvesting going on and that I would get spam to the address. I am very surprised at the volume and type of spam, though. I’m getting a lot of chinese language spam, a lot of “join our business organization” spam and mail claiming I subscribed to receive their offers.
Surprisingly, much of the spam to this address violates CAN SPAM in some way shape or form. And I can prove harvesting, which would net treble damages if I had the time or inclination to sue.
It’s been an interesting experience, putting an unfiltered address on the website. Unfortunately, I am at risk of losing your questions because of the amount of spam coming in. I don’t think I’ve missed any, yet, but losing real mail is always a risk when an address gets a lot of spam – whether or not the recipient runs filters.
I’m still pondering solutions, but for now the questions address will remain as it is.

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Why do ISPs do that?

One of the most common things I hear is “but why does the ISP do it that way?” The generic answer for that question is: because it works for them and meets their needs. Anyone designing a mail system has to implement some sort of spam filtering and will have to accept the potential for lost mail. Even the those recipients who runs no software filtering may lose mail. Their spamfilter is the delete key and sometimes they’ll delete a real mail.
Every mailserver admin, whether managing a MTA for a corporation, an ISP or themselves inevitably looks at the question of false positives and false negatives. Some are more sensitive to false negatives and would rather block real mail than have to wade through a mailbox full of spam. Others are more sensitive to false positives and would rather deal with unfiltered spam than risk losing mail.
At the ISPs, many of these decisions aren’t made by one person, but the decisions are driven by the business philosophy, requirements and technology. The different consumer ISPs have different philosophies and these show in their spamfiltering.
Gmail, for instance, has a lot of faith in their ability to sort, classify and rank text. This is, after all, what Google does. Therefore, they accept most of the email delivered to Gmail users and then sort after the fact. This fits their technology, their available resources and their business philosophy. They leave as much filtering at the enduser level as they can.
Yahoo, on the other hand, chooses to filter mail at the MTA. While their spamfoldering algorithms are good, they don’t want to waste CPU and filtering effort on mail that they think may be spam. So, they choose to block heavily at the edge, going so far as to rate limit senders that they don’t know about the mail. Endusers are protected from malicious mail and senders have the ability to retry mail until it is accepted.
The same types of entries could be written about Hotmail or AOL. They could even be written about the various spam filter vendors and blocklists. Every company has their own way of doing things and their way reflects their underlying business philosophy.

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