North American Network Operators Group
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Re: ISP wants to stop outgoing web based spam

  • From: David Andersen
  • Date: Wed Aug 09 14:29:53 2006
On Aug 9, 2006, at 2:15 PM, Barry Shein wrote:



I think what was being talked about was that a lot of spam now comes
as embedded images which unpack into ads for the usual stuff. It's
actually been going on for a few years but I guess as the other stuff
gets more and more effectively blocked this form becomes more salient.

Thus far I don't know of any good filter for these.

Common spam software seems to rotate or vary these slightly so it's
not as simple as comparing to one you've seen before. Since the image
formats are compressed, usually gif, tiny changes can ripple through
the entire encoding.

Now we'll have to throw our inbound email through an OCR.

Then the spammers will start rotating the text or changing the background.

So we'll write a better OCR that can see through such transformations.

At which point, the spammers will be happy, because we'll have given them a tool to break Captchas.

Hmmm...

(Or just reject mail with images in it. :)

-Dave

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