For those of you who are unfamiliar with them, CAPCHA’s are those pictures at the end of forms with random letters and numbers which you have to enter into an accompanying text box.  The purpose of this is to determine humans from bots or automated scripts.  Well, it’s intention is really to prevent bots and automated scripts from using their services, but that is becoming more difficult to do.  While there are tools that can decipher these CAPTCHA’s, a group of spammers decided to take a different approach: have people fill in CAPTCHA’s for them.  So what they did was develop a virtual stripper and for each CAPTCHA you enter, another article of clothing comes off.  The crazy thing is that since it is in an article, chances are that it’s working.

October 30, 2007 (Computerworld) — Spammers are using a virtual stripper as bait to dupe people into helping criminals crack codes they need to send more spam or boost the rankings of parasitic Web sites, security researchers said today.

A series of photographs shows “Melissa,” no relation to the 1999 worm by the same name, with progressively fewer clothes and more skin each time the user correctly enters the characters in an accompanying CAPTCHA (Completely Automatic Public Turing Test to Tell Computers and Humans Apart), the distorted, scrambled codes that most Web mail services use to block bots from registering hundreds or thousands of accounts. Spammers rely on Web e-mail accounts because they’re disposable; by the time filters have blocked the address, the spammers throw it away and move on to another.

The CAPTCHAs that Melissa feeds to users are, in fact, legitimate codes snatched from Yahoo Mail’s signup screens, said analysts at Trend Micro Inc. The hackers, frustrated at their inability to come up with a way to automate account registration, are getting users to do their dirty work.

“They’re using human beings in semi-real time to translate CAPTCHAs by proxy,” said Paul Ferguson, a network architect at Trend Micro. “You have to give them this, it’s clever.”[more]

Tags: Spam