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Spammers Are Early Adopters of SPF Standard

nazarijo writes "In an article entitled Spammers using sender authentication too, study says, Infoworld reports that a study by CipherTrust shows that SPF and Sender ID (SID) aren't nearly as effective as we expected them to be when combatting spam. The reason? Spammers are able to publish their own records, too. 'Spammers are now better than companies at reporting the source of their e-mail,' says Paul Judge, noted spam researcher and CipherTrust CTO. Combined with low adoption rates of either SID or SPF (31 of the Fortune 1000 according to CipherTrust), this means that the common dream of SPF or SID clearing up the spam problem wont be coming true. Wong, one of the original authors of SPF and a co-author of SID, says that it was never intended to combat all spam. Weng, another researcher in the space, says that this is just one of the many pieces of the puzzle needed to combat spam. Various SID implementations exist, including a new one from Sendmail.net based on their milter API, making it easy for you to adopt SID and try this for yourself."

14 of 249 comments (clear)

  1. The point of SPF by pikine · · Score: 5, Insightful

    ... is not to block spam, but to identify the source of an e-mail. Spammers can definitely identify themselves if they so choose. I think it is still a welcoming trend.

    --
    I once had a signature.
    1. Re:The point of SPF by forevermore · · Score: 3, Insightful
      The point of SPF is ... to identify the source of an e-mail

      This point needs to be emphasized. The whole point of SPF is to prevent spammers from falsifying return addresses. If they want to publish their own legitimate SPF records, then by all means let them. Then we can just block them by their domain names without any fear of blocking legitimate email.

      --
      Do you really need reason for beer? Wingman Brewers
  2. Isn't this what we want? by Carnildo · · Score: 5, Insightful

    Isn't putting up SPF records exactly what we want spammers to do? If they've got SPF records, running an RBL against spam domains should be easier and more accurate.

    --
    "They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
    1. Re:Isn't this what we want? by YankeeInExile · · Score: 3, Insightful

      Well, a quick off-the-cuff idea is thus: Expand SPF or its moral equivalent to offer a web-of-trust style interface. That is: Each piece of email comes with a pointer that says, in effect, This piece of email is from mydomain.com ... people who think that mydomain.com is cool are yourisp.com otherisp.com white-hat-geeks.net

      So, I suppose what I'm proposing is a distributed whitelist.

      --
      How does the Slashdot Effect happen given that no slashdotters ever RTFA?
    2. Re:Isn't this what we want? by Carnildo · · Score: 3, Insightful

      Assumed it takes an hour to add a domain to an automated blacklist. I think it could be done in five minutes or so, but let's be generous:

      24 domains/day * 365 days/year * $12/domain = $105,120

      That's a hundred thousand dollars they didn't used to need to spend each year. Automated blacklisting in five minutes boosts the costs to well over a million dollars a year.

      --
      "They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
    3. Re:Isn't this what we want? by AtOMiCNebula · · Score: 4, Insightful

      But now, spammers have to invest money in what they're doing. It doesn't matter if it's much or not, but it is something. It's more than what they were paying before, so unless they don't mind cutting into their profit margins, they're going to be affected by this.

      Compare what it used to be with how it is now. It used to be that spammers could use any domain they want. Now they can only use domains they own (assuming they're using SPF), and as soon as one domain is RBL'd, they're going to need another domain. More work for the spammers. And more cost too.

      What I'm trying to say is that, yes, domains are cheap. But now they're paying for domains that they didn't have to before.

    4. Re:Isn't this what we want? by Prong · · Score: 3, Insightful
      You are partially correct. It does marginally increase the cost of doing business for spammers, but remember that the major spam houses have the capital to lease major bandwidth, and have for some time. Having to madly swap domains to get is only going to swamp smaller spammers with enough extra cost to kill them. The big boys are going to keep chugging along, and the big boys are the biggest source of spam (obviously).

      What I like about SPF is that as larger ISPs adopt it, I can stop worrying about accidently filtering their domains just because of the domain name on the From: header. I'm fully aware I'm still going to have to filter, but it's nice to know that "tightvagina@yahoo.com" actually came from an authorized Yahoo mail server. Combine that with any number of of rational filtering schemes, and you have a much lower false positive rate, with the bonus being that you didn't have to take the whole message from a sender who fails the SPF check.

  3. No one claimed it would end spam by Anonymous Coward · · Score: 3, Insightful

    What it does end is domain spoofing (joe jobs), and it adds a level of accountability. If spammers are using their real domains, great. We go to their registrars, most of which have anti-spammer policies, and we get it yanked. If it costs the spammers money, it's a good thing.

  4. But that's not the point of SPF by hypnagogue · · Score: 5, Insightful

    The point of SPF was not to eliminate spam, but to eliminate spoofing. If successful, this is enables effective and cheap spam filtering by forcing spammers to use domains that can easily be blacklisted.

    In other words, SPF is working correctly, brighter tomorrow expected, move along, nothing to see here.

    --
    Liberty you never use is liberty you lose.
  5. SenderID != Spam Solution by Manip · · Score: 3, Insightful

    SenderID is not designed to combat spam (although many uninformed individuals think it is), it was designed to fix a fundamental problem with the E-Mail system.

    You can not guarantee that an E-Mail originated from the source it said it did.

    Which effectively makes black-lists useless.

    With SenderIDs you are able to build effective Black-Lists/White-Lists because you can guarantee that an E-Mail came from the location it said it did. And thus decrease the amount of spam.

    I'm not sure who wrote this 'study' but the fact that I know more than them says a lot.

  6. Appearantly, some people missed the point... by Otto · · Score: 4, Insightful

    If spammers are now forced to identify themselves in their emails, by means of having a domain and publishing SPF records for that domain, then good.

    That was the entire point.

    In combination with anti-spam laws, now we have the ability to actually identify the spammers flooding our inboxes and take legal action against them for doing so.

    There is no technological means that will allow random people to email you and yet prevent them from emailing you spam. Technology is simply not capable of distinguishing spam from non-spam with a 100% success rate. We can get really close, but there will always be false-positives and false-negatives in any system. And any system is vulnerable to clever hacking around the filter. You can make it terribly difficult to do so, but you can't make it impossible.

    The goal of SPF never was to stop spam, it was to force somebody who sends you email to be accountable for doing so, by providing a method to track down who they are. At least, it's a good start for this sort of thing.

    --
    - Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
  7. Re:A Change Needs to be made by ZorbaTHut · · Score: 3, Insightful

    How would you change it?

    Why can't these changes be integrated into SMTP-as-we-know-it?

    It's all very nice to say "it needs to change", but until you explain why changing it is the best solution - or even vaguely useful - it's not going to happen.

    --
    Breaking Into the Industry - A development log about starting a game studio.
  8. Important notice: please update your USBank info! by coyote-san · · Score: 4, Insightful
    There are four separate "spam" problems:
    • Unsolicited but legal mail from a legitimate mail server
    • Unsolicited mail (legal or not) from hijacked systems, open mail relays, etc.
    • Viruses
    • Fradulent mail

    SPF can be circumvented in the ways we're already seeing for the first category, but it should knock out the second two (and probably related) problems.

    As for the final one... law enforcement may still not take phishing seriously. But I bet Citibank, US Bank, et al do. They're probably losing millions of dollars cleaning up the mess left by phishers, and that money would go a long way towards making phisher's lives miserable and cautionary tales for others. These organizations are large enough that phishers can't even hide behind international borders - piss of Citibank by protecting phishers and that bank may decide that it's not worth doing any business in your country.

    --
    For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
  9. I won't pay $300/year to send mail by Wesley+Felter · · Score: 3, Insightful

    'nuff said.