How to combat small-font-spam..

By Angsuman Chakraborty, Gaea News Network
Thursday, March 3, 2005

A recent trend in spamming observed in Larry Seltzer’s blog and elsewhere is to use very small font size characters to create an ascii art to provide spam messages.

What is interesting is that unlike the example above spammers can use legitimate email messages chosen randomly from computers they have hacked to create the ascii art. Currently filters including naive bayesian are unable to filter messages which appears as normal emails.

The only way I can think of to filter such messages is to look for effective size of the fonts in the message. And if the size is not normally humanly readable (anything smaller than 7px should be a good first guess) should be treated as spam.

Any other ideas?
Filed under: Spam Watch
Discuss Bellow
Discussion

angsuman
March 17, 2005: 7:24 pm

@Jonas and @Denis
True. But you also miss many colorful messages from your friends and important newsletters etc.
As Rabindranath Tagore (famous Bengali poet and Nobel laureate) once said in a small poem (roughly translated):
“We close the door to lies, truth says you have also closed the door for me”

@Jonas
I like the idea of asking friends to send zipped version of html. But how will I tell all my clients :)


Denis de Bernardy
March 9, 2005: 4:01 am

Yes, one: read emails as plain text. It has the additional benefit of warding off many viruses.

Jonas Karlsson
March 3, 2005: 10:42 pm

Or just force your mail client to discard the html and ‘rich text’ content of all mails. If someone wants to send me a html file, they can zip it up and attach it to the mail…
YOUR VIEW POINT
NAME : (REQUIRED)
MAIL : (REQUIRED)
will not be displayed
WEBSITE : (OPTIONAL)
YOUR
COMMENT :
 
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