[RC5] spam

Denie Andriessen D.Andriessen at pink.nl
Mon Jun 21 02:24:35 EDT 1999


>>> Use a technique similar to those of web-page counters... create a
>>> script that converts the email address text to a GIF.  Problem
>>> solved.
>>
>> Very good idea.. This would make the automated harvesting of those
>> emails quite impossible.
>
>It would still be rather easy actually, although admittedly it would be
>more work for the spammer.  Once you know the font being used and have
>a sample of every character in that font (easy) it would not be hard to
>write a program to compare blocks of pixels with those which are
>already known and to reconstruct the email addresses.
>
>It's just about the simplest form of image recognition.


Well, it's always possible to get back to the origional adres, automated or
not,
but I wonder if the average spammer would take that amount of time to gather
just 175.000 emails, when (s)he can get emails using 'standard' tools/bots
to
harvest a magnitude order more emails... It's the same as trying all keys on
an encrypted message, sure you will get there, but is it worth it ? (to the
spammer
in this case)

Just for the sake of this discussion, I think even if the addresses will be
put on
the web as GIF's, there will be people that build a tool to show it can be
converted back.. That's the whole mentality of (some of) the people with
d.net.

Maybe I'll even try. The 'convert' tool on Unix (maybe even DOS etc) can
conver a GIF
to BMP, from there you can read the dimensions from the image, chop it in
parts
where there's a vertical 'whitespace', (As BMP is bitmapped), identify
manually all
characters in the used font once and build a table of it, compare all
address
'parts/characters' to the table, and there you have it. A semi automated
GIF-email
convertor for d.net GIF's.. And offcourse, add a nice web-form, where you
can enter
the URL of the GIF, or page with the GIF's on there, a script retrieves the
page/GIF's,
analyses them, and reports the emails back or directly send the spam mesage
to
all discovered emails,...and bob's your uncle. (Well bob is not my uncle)

Cheers, (*)

Denie Andriessen

*: J.P.Chenet '98(*2), Cabernet Syrah, Vin de pays D'oc, 12% Vol, 75cl.
*2: The above stament is not Y2K compliant.

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