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Re: Keep getting subborn spam with random words

2004-03-10 08:24:56
    Marco> Graham answered the same thing as you:

    >>> I would not worry too much about spammers appending customized
    >>> text. They might append random text, or the same text to every
    >>> email, but anything that requires them to treat each recipient
    >>> individually is too expensive for them.

    Marco> However, I'm not sure yet about this. If one contributes often to
    Marco> a mailing list, how much hassle it is to automatically append a
    Marco> different real message from that list archives to each spam? They
    Marco> could also do this on a list basis. What do you think?

A number of things come to mind:

    1. Most people have little or no persistent public presence on the
       net other than sending/receiving email.  (The members of this
       list probably represent a small minority of net users.)  For
       example, I just googled for my wife's email address.  It
       returned nothing.  Still, she does get some spam.  Her email
       address was probably sucked into spam email collections by
       dictionary search (guessing email addresses - her username is
       "ellen") or by a worm/virus harvesting email addresses out of
       address books.  That suggests that looking for suitable
       per-email text will not pay off.

    2. Bandwidth is still fairly expensive.  Spammers probably consume
       most of their existing bandwidth sending out mail.  Reducing
       the outflow of email will lower their overall revenues.  Adding
       more bandwidth so they can search for hammy text to associate
       with email addresses is expensive.

    3. As I mentioned before, static text won't cut it.  If they add

           The normal flow of control is when you fall out the bottom
           of the loop when your control test goes false.  Breaking
           out of the middle is indeed an exceptional circumstance; it
           is an exception to the normal flow of control.  People tend
           to think of exceptions as errors, but they don't have to
           be.

       to each spam message they send to skip(_at_)pobox(_dot_)com I will 
quickly train
       on the few false negatives that slip through and shift the spamprob
       of each of the hammy words in the paragraph in the direction of spam.
       That paragraph will cease to be effective and the spammer will have
       to find a new one.

-- 
Skip Montanaro
Got gigs? http://www.musi-cal.com/submit.html
Got spam? http://spambayes.sf.net/
skip(_at_)pobox(_dot_)com

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