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Will Solve Captcha for Money?
alx_lo writes "Captchas are a nice idea to protect your blog or guestbook from being spammed by robots.
But what good is this protection when you can hire "data entry specialists" to solve captchas for $0.60 per hour for 50 hours a week?
Anyone here who can think up a solution that does not include drastically changing the global economy? How about captchas that require cultural background knowledge to solve?"
I admin a PHPBB-based forum and the spam (from bots) was getting out of hand. They were going through the built-in CAPTCHA with no problem. The solution ended up being that I had to modify the registration form so that it wasn't just the default form. Throw a couple of oddball questions on the form, make them required, and bots can't deal with it since the bot script can't account for deviations from the norm.
Transistors and Beer!!
Yesterday, I saw a presentation by Dr. Luis Von Ahn (developer of the ESP Game, and other CAPTCHA type games). He claimed that spammers and porn companies are willing to pay about $2.50 an hour for 720 CAPTCHAs an hour, or about 1/3 cent per CAPTHCA. (The CAPTCHA solcing is needed to create more free email spamcounts.) I don't know why people would solve them for so much less...
It looks as if most spammers operate in two phase: first they collect valid guestbook URLs, and then, several weeks after, they spam those. Probably it's not even the same people doing both phases, the first could be selling lists to the second.
So, a couple of weeks ago, I moved my guestbook to another URL, and since then, I've got almost no spam (only 3 spams in 4 weeks, versus more than 10 per day before...). And apart from a simple keyword filter, the guestbook has no other protection (i.e. no captcha whatsoever).
So the real problem is coming up with CAPTCHAs in real-time with no permanent (this session ID) correlation made between the image link and the answer. Then hiring "slave labor" to make this mapping for you will be completely useless.
Yes and no - That solves the problem of precreated CAPTCHAs, by throwing CPU time at it, but the FP's complaint doesn't actually involve what CAPTCHAs solve.
CAPTCHAs, if effective (which a market for human solvers suggests), only prove that a human has responded. If a human solves it for pay on behalf of a spammer - The CAPTCHA worked perfectly. Virtually every suggestion on this topic has missed that key point. Using culturally-dependant information, or judgements of aesthetics, or awkwardly-phrased audio clips, or even time-wasting math problems, all still just prove that a human answered the question.
The real problem here involves the misuse of CAPTCHAs by those who assume they do something which they don't. They don't weed out "undesireables". They weed out non-humans. It really doesn't matter how complex you make them; if a human can solve it, you still have the same underlying flaw - Namely, that we have a HUMAN enemy in this battle.
Instead, we need to exploit a human vulnerability - Mortality. We need to hunt down spammers and kill them, slowly and painfully. We need to torture their wives and kids in front of them, then string the lot of 'em up in town squares as an example to others. We then need to hunt down all the companies funding these spammers as a form of advertising and castrate their boards of directors.
Or better yet, we need to trick them into running P2P nodes and let them and the RIAA weaken each other to the point that we can easily eliminate the winner.