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Cracaked CAPTHAs!!! oh no! (Score:5, Interesting)
Re:Cracaked CAPTHAs!!! oh no! (Score:5, Insightful)
I hate the fact that a computer can view these things better than I can. Lately, a lot of the CAPTCHAs have become unreadable by human viewers.
They don't view it better than you, they just do not get impatient from failing 4 out of 5 times.
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And they share better. (Score:3, Interesting)
Put 1,000 computers on the problem and allow them to share information from their successes ... and you've cracked a CAPTCHA implementation.
And there are hundreds of thousands of zombies out there.
Re:And they share better. (Score:5, Interesting)
The best way I've seen that captcha's got broken are by "free porn sites". The web site is what is cracking another captcha. When it gets a captcha to solve, it passes it to one if it's "porn viewers" - "please type the word that this captcha says in order to prove you are old enough to view the porn". Then the porn is displayed and the bot running on the website has a potential solution made by a human to do it's botting with.
This method will suffice to crack ANY CAPTCHA!
--jeffk++
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Re:And they share better. (Score:5, Interesting)
Absolutely correct.
I run a mid-sized web development shop. A few years ago we were doing mostly retail sites. Vanilla and boring but we worked it down to a science and had some really great "modules" that made these sites super profitable for us. Of course, everything has its seedy side and with retail it was SEO.
Everybody wanted it. About 80% of our customers were of the "Do whatever, just ideminfy me" stripe. (And these are established companies paying high 5-figures for these sites). We drew our own demarcation about what we would and wouldn't do. (Excessive Internal-link structure is OK, zombie sites are not).
Now most our work is social networking.
We, too, followed the "rise" of CAPTCHA and we've been happy with our results. We always used a custom CAP for each site, and we tried to keep them relatively readable, being of the belief that making it too hard will only keep out Humans: If somebody wants to crack it, they will.
We still use them regularly. I noticed that about a year ago we actually had people begin to request them specifically. (Isn't that what Buffett said about the home mortgage mess? When the regular joe's started flipping houses, he knew it was over?)
Anyhoo, I think the real fault in CAP's is that they worked too well. They became too big of a target. Now, we try to mix and match a number of different techniques to identify humans.
Solutions range from dirt-simple: An input box named, say, "City" that has a label that reads "13 plus 8 equals:" or "What is the 3rd word on this page?"
To the more complex "what is the color of the front-door in this picture?"
We have a simple library we use for these things that pulls the questions (and, if applicable, the pics) from a Database of about 25,000 different turing tests.
The thing is, none of them are too complex. Any mediocre programmer could write an application to crack it. But your bot will probably never see that same exact question again, so it becomes irrelevant.
And, to tie it in to the parent, we chose this technique precicely because of what we learned from CAPs. Before there were software hacks, there was the "porn hack" and the "sweatshop labor hack."
In this case, when a bot the site, it's fairly difficult for it to even detect which item is the turing test. We auto-generate the location and even the name of the form field so it's always a bit different.
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SEOs - Lying to Robots so Robots Lie to Humans (Score:5, Interesting)
Search Engines help humans find web pages that the humans might find interesting, and they do this by having robots spider the web looking for patterns. Search Engine Optimizers try to get humans to read their customers' web pages in three ways:
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Re:Cracaked CAPTHAs!!! oh no! (Score:4, Interesting)
Or from failing 999 times out of 1,000. Computers have an infinite amount of patience. Security schemes that don't acknowledge that are doomed to failure.
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Re:Cracaked CAPTHAs!!! oh no! (Score:4, Insightful)
Looks like I'm not the only one not smart enough - they replaced this CAPTCHA with some "Happy Hour" mode, which didn't require any form.
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Anyone usinging specialised tests? (Score:5, Interesting)
Of course this solution isn't going to work for gmail - which seems to be the preferred email provider for the spam signups I do get these days.
Make Them Write (Score:4, Funny)
I've toyed with the idea of making users write a 500 word essay on a random topic. I would then send this to my high school English teacher, and if it got maybe a B or above I would consider it legit.
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Re: (Score:3, Informative)
While that's a class of problem that's tricky (though not impossible) to address, giving you the choice of a few different animals it might be is insufficient. Even if there are 10 choices, random guessing will be right 10% of the time, and that's enough for spammers. Subjective answers (showing a picture of a dog and having someone type "dog") are tricky because not everyone will type "dog", and you don't want to reject humans.
The current design fits the requirements well because the answer is distinctly o
Re:Anyone usinging specialised tests? (Score:5, Insightful)
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A good solution here... (Score:5, Interesting)
A good solution here is to include this as part of the turing test itself.
As I mentioned upthread, I'm a partner in a web dev shop. We do a lot of social networking (of course) and about a year ago we developed a utility to create just this type of turing test. For example, we'll have a picture, and ask the question "What is the color of the 3rd fish from the left?"
What we do, is we pair these tests on a page. We'll include a known test, like the one above. And we'll also show an unclassified image and we might ask "how many people are in this picture?"
There is no wrong answer for that test, and their answer is recorded. Soon, that same question will be asked for that same picture. As soon as its confirmed 2 times, it gets classified as having n people. Soon after it would be displayed again asking "how many females are in this pic?" or "what color shirt is the person on the right wearing?"
When we created the app, the DB had about 5000 turing tests in it. We then attached a DB of about 100,000 images that were pre-classified but not to an extent that would allow us to write a test off it.
Now, after a year in use across a couple dozen moderately trafficked websites, we have nearly 25,000 turing tests. All 20,000 new tests have been created thru the technique I described above.
The real reason we did it wasn't to save on some development costs. We could've hired temp workers and paid them $8 an hour to classify pictures.
We did it because I believe strongly that the key to simple turing tests like this is a large corpus of data. If a bot only encounters the same test once or twice EVER, then the problem becomes difficult to solve. This is like the ANTI-CAPTCHA.
CAPTCHA was all about taking a specific technique to its maximum extent: Challenge a computer system by taking a narrow field (OCR) and pushing it beyond the current state-of-the-art.
These tests are all about a general technique thats broad where CAPTCHA is just deep.
The only way to build a bot to solve each test in our DB would be to give it genuine intelligence. It would have to be capable of determining context, reference, connotation, image ID, etc.
As a programmer, if you say "Here's a captcha, write a program to solve it" I wouldn't know HOW, but I'd at least have an idea of where to begin.
Now, if you show me a picture with the turing test of "What object is in the hands of the 3rd woman from the left" ... well... i wouldn't know where to begin.
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Re:A good solution here... (Score:4, Insightful)
"There is no wrong answer for that test, and their answer is recorded. Soon, that same question will be asked for that same picture. As soon as its confirmed 2 times, it gets classified as having n people."
How do you know that those 2 confirmed times weren't bots, and that you've just allowed those bots to effectively choose the answer to your question?
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Re:Anyone usinging specialised tests? (Score:4, Insightful)
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Re:Anyone usinging specialised tests? (Score:5, Insightful)
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Re:Anyone usinging specialised tests? (Score:4, Funny)
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Re:Anyone usinging specialised tests? (Score:4, Funny)
No.
You see there is an ongoing war against the postmasters by the webmasters. I am a postmaster, and I get roughly 300ish spam mails per site.
And the webmasters sit and chuckle. Bastards, they could make it stop!
But they don't... animals...
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Re:Anyone usinging specialised tests? (Score:5, Interesting)
what is the opposite of up?
what day is after friday?
what does seven plus three equal?
what letter of the alphabet comes before d?
how many wheels does a bicycle have?
what is the third word of this sentence?
These are generally difficult for computers to solve, can be programed to have permutations, and since the quiz answer can be tied to the account, if a particular question or style is getting spammed frequently, it can be removed from the list of questions.
It's an arms race, and this system won't work forever, but it's fairly easy to implement and fairly difficult to overcome.
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Re:Anyone usinging specialised tests? (Score:5, Funny)
what is the third word of this sentence?
No, its the first.
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Mix it up a bit? (Score:5, Interesting)
Combine it with a mix of simple math and image recognition? I.e.
"What colour hair does the (2+four)/3 girl from the left have?"
Hell, skip the math part if that's too easy.
Re:Mix it up a bit? (Score:5, Insightful)
CAPTCHAs need to be able to be generated algorithmically by a computer, but not answered by one, which is a surprisingly difficult problem. Anything that requires human intervention on the creation of each variation is doomed to fail because spammers have more free time than you do.
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Re:Mix it up a bit? (Score:5, Funny)
Prove that a 3-manifold space has the additional property that each loop in the space can be continuously tightened to a point then it is just a three-dimensional sphere.
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Re:Mix it up a bit? (Score:4, Funny)
I can't wait until someone's daughter tries to make an account on Barbie's Horse Talk website and is presented with the following CAPTCHA:
Prove that a 3-manifold space has the additional property that each loop in the space can be continuously tightened to a point then it is just a three-dimensional sphere.
So thats why Grigori Perelman [wikipedia.org] decided to solve that CAPTCHA.
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Re:Mix it up a bit? (Score:4, Funny)
And I can't wait until someone's daughter answers back:
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Re:Mix it up a bit? (Score:4, Insightful)
"On the internet, only CAPTCHAs know you're a dog." Because, of course, there aren't any color-blind people on the internet...
First, hair color is a terrible test... You've got about a 24% chance of getting it right without looking...
Putting together a set of images with full extensive descriptions such as that would be prohibitive, while numbers and letters can be pretty easily automatically generated.
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Re:Mix it up a bit? (Score:4, Funny)
Now if you had said,
What color of hair does the 3rd girl on the right have,
A: green
B: brown
c: Blond
D: I drive a ferrari, I don't care about hair color!
you would only eliminate about one eighth
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Captchas are only good for protecting cheap stuff. (Score:5, Insightful)
CAPTCHAs are only able to protect things worth $.0025, no matter how good they are. Simply because at about that price, you can pay humans to solve them for you.
Thus for preventing mail spam, it can work. But to prevent, say, bots from harvesting Ticketmaster, they will always fail, no matter how good they are.
Gold Farming as CAPTCHA equivalent (Score:4, Informative)
Humans may not be as fast as robots, but they can be surprisingly cheap. There's enough of the world where $1/hour* is an attractive wage that speak some English, and if the people there can solve a CAPTCHA in 9 seconds, that's at the $0.0025 price level that Nick was referring to. (Hi, Nick!)
If you're a scammer and there's a website that you want to crack, but it's not big enough to pay somebody to develop an algorithm for (either because the CAPTCHA's too hard or changes too often etc.), you can find some corrupt Nigerian generals' orphaned children who'll do it, or some Chinese guys who are tired of beating up monsters to get gold pieces or magic swords.
I don't know the going price of zombies or mail relay accounts, and it's probably dropping at faster than Moore's Law, but some sites are probably worth attacking.
* "Make good money $5 a day... Made any more I might move away..."
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Depressing (Score:3, Insightful)
Re:Depressing (Score:4, Interesting)
It's depressing to me that things like viagra spam are still profitable enough to make spamming them financially useful. Sure, the way the economics of it work out you only need a really low response rate to break even, but hasn't everyone already gotten enough of those emails? I'd imagine that whatever market there is for sketch viagra distributors would be saturated by now.
At least with phishing spam I get to see new scams on a regular basis (some quite cleverly disgused too). But some of the more vanilla spam just seems pointless.
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Still useful (Score:5, Insightful)
CAPTCHA is still useful for small to medium sites that aren't specifically targeted. Your average blog, for example, is only hit by random bots that try to get quick and easy posts. Only the largest sites like GMail need to find something better today.
For example, I use reCAPTCHA [recaptcha.net] on DocForge [docforge.com] to block the standard wiki spam bots. Since my site's not large enough to be under heavy attack very little gets through. Someday CAPTCHA may be so easy to break that everyone's at risk, but not today.
The best part is.. (Score:5, Interesting)
Spammers are cracking some of the hardest problems of AI research.
How can they do that, and yet all the great academic minds can't? Two things:
* funding
* a willingness to use "anything that works"
What's really scary is that, in the end, spamming may turn out to be an agent of good.
But they're not, really (Score:3, Informative)
Much of this is finding a way to brute-force the methods used on particular sites, overwhelming randomness, etc. It's not really a computer reading any difficult text.
A dumb question: (Score:5, Interesting)
Howcome /. is so spam free?
Do the hackers just not care about us,
or:
is this like one of those "safe zones" where geeks and hackers can hang out as long as nobody asks or tells? (looks at guy to his left..."say is that a CAPTCHA in your pocket or are you just excited to be here...")
Re:A dumb question: (Score:5, Informative)
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Re:A dumb question: (Score:4, Interesting)
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Re:A dumb question: (Score:5, Funny)
Howcome /. is so spam free?
You must be new here.
and blind.
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Suggested New CAPTCHA method. (Score:3, Interesting)
fall of open email (Score:5, Insightful)
it is no wonder that the "under 25" crowd now says "myspace me" or "facebook me" and no longer use email. why would they?
in a globally connected world with several billion possible users - open email simply won't work much longer.
when we need are permission based systems - ones in which people need permission before they can contact another person. it would eliminate spam entirely, by integrating whitelists into mail clients. because no one has built a system like this that leverages and extends existing email servers - private organizations leveraging social connections have moved in to fill the gap. sadly, because facebook messages and myspace messages are not built on an open standard - you have to go through those companies to contact people.
Re:fall of open email (Score:5, Funny)
it is no wonder that the "under 25" crowd now says "myspace me" or "facebook me" and no longer use email. why would they?
Whatever happened to giving someone your phone number and actually talking to them. I asked a girl for her number the other night and she gave me her myspace address. Thanks, but no thanks. At least make the effort and give me a fake phone number if you don't ever really want to talk to me again.
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OpenID signatures (Score:4, Interesting)
Integrate OpenID based signatures with email by inserting a line into the email header.
Not a new idea, its the same old 3rd party trust situation-- so clearly the trusted OpenID servers would be targeted; however, if you added a simplistic peer ranking system on those user IDs (extending openID a little) then the bad IDs would get ranked down by real people.
This would also provide a means for verification for multiple emails used by the same individual's OpenID which could shield their actual identity (but not any better privacy than you have already.)
Additional headers for point of origin server could also be useful as some servers are less trust worthy than others (note: spam ranking is fuzzy and a slight nudge either way near the threshold value can make a noticeable difference. ) Server identity issues are already being worked on; but emails are not tied securely to the original server.
I'd like to see a standard email header line for spam ranking (0-100?); I'm sick of these "{spam?}" lines inserted in subject lines that I see time to time.
An OpenID based solution would get OpenID heavily tested since spammers may solve the big AI problems as well as letting us know where to get Viagra.
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Just use (Score:5, Insightful)
Re:Just use (Score:5, Insightful)
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turing test (Score:4, Funny)
The first thing to actually pass the Turing test will probably be a spam-bot. Isn't that disgusting?
The Irony (Score:5, Funny)
The irony about this is that a CAPTCHA is a Turing test, a form of authentication designed to prove that a human is making the request. Given that some CAPTCHAs are rapidly becoming too hard for people to read, the outcomes of the tests are reversed - humans cannot win the test, only computers.
I have CAPTCHAs on my blog, but only deny posters who actually fill them in. Goes a long way to deterring spammers.
M
Re:The Irony (Score:5, Interesting)
Interesting.
A few months ago I tried to post on a blog (sorry, I forget which one), entered the CAPTCHA and got a message that I was a suspected bot and my IP address was banned from posting for 48 hours.
I went back and carefully read the terms of use (just above the posting window) and buried in the middle of the terms was the phrase, "Do not enter the captcha, instead enter the first three letters of the fifteenth word in the second paragraph followed by the third word after the eighth word in the first paragraph in all capital letters."
A neat idea, but I suppose it won't be long before that one is cracked as well.
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On sites like gMail.. (Score:5, Insightful)
On gMail some simple rules should suffice. Don't allow a brand-new account to send out more than a few (20?) emails a day. Make sure that most of the email varies. Make sure the account gets and reads email as well as sends it, and that the email is accessed.
The trick is, you keep rotating these measures and don't tell anyone just what they are. You don't automatically disable anyone who breaks the rules, you just hold on to any large number of similar messages until a human reviews them--possibly through some mechanism similar to the "picture matching game" where multiple people identify a message as spam.
If it's determined to be spam, never tell them you caught on, just stop email from that account from being sent, silently. Log the ip addresses and use them to help you identify other accounts from the same computer if possible.
You could also use the ip addresses to notify people that they are a spambot next time that IP address is used to look up something on any google service.
Wow, that's a broad action with a lot of chances for failure, but I bet it could be refined enough to work--and worst case failure isn't bad at all--just one time when you go to search google you get a warning page back instead of your search results.
Really this just takes some dedicated effort and creative thinking by a strong, creative engineer with some power within google (I know there are quite a few of those)
Misleading phrasing (Score:5, Insightful)
This is misleadingly implies that CAPTCHA somehow enables spammers. On the contrary, broken CAPTCHA does not enable spammers to do anything they couldn't already do -- we're just back where we were before CAPTCHA.
And to be fair, CAPTCHA is still reducing the rate at which attackers are able to create accounts, keeping some smaller, less sophisticated players out of the game entirely, and protecting lower-value targets (e.g., most small-time bloggers with comment spam problems still see a drastic improvement when they set up CAPTCHA)
If everyone stopped using CAPTCHA, the spam problem would get noticeably worse.
Offshoring CAPTCHA solving (Score:5, Informative)
The spammers have a new solution to CAPTCHAs in place - offshore outsourcing. [ezadsuite.com] This has become a sizable operation. System status earlier today:
Current Status: Volumes are exceedingly high. -- Automatically dispatching more labor
Queued Captchas: 91
Total outsourced volume: 4564301
This service is integrated with Craigslist auto posting tools, allowing high-speed spamming of Craigslist. It's also used for other services, like obtaining GMail accounts.
Even Craigslist's callback-by-phone system is starting to crack. Temporary phone numbers for Craiglist verification, provided by marginal telephony providers, have dropped to $1.50 in bulk.
The overall effect of Craigslist's new protections is that the cost of spamming has gone up, enough to slow down the low-rent operators but not by enough to stop it.
As I've pointed out previously, Google plays a central role in this. [slashdot.org] Google's services provide a facade of anonymity for scammers to hide behind. GMail for anonymous mail, YouTube for anonymous infomercials, AdWords for anonymous advertising, Checkout for anonymous money transfer, and Blogger/Blogspot for anonymous redirectors to zombie machines are all valuable services for scammers and spammers. All those services are used heavily by Craigslist spammers.
Others have provided some of the same services, but the competing services had bad reputations. Anybody trying to do business via Hotmail just had to be phony. Many mail agents just block all Hotmail mail. Anyone running a business off of "freewebpage.org" probably wasn't someone you'd want to deal with. So you had some strong indications of lack of legitimacy there.
Google, though, still has a good reputation. The combination of Google's reputation and low customer standards offers a great opportunity for scammers, and they're taking it.