An anti-spam technique that was developed to block robots from spamming a site. CAPTCHA works by asking the user to answer a question or solve a problem (such as reading a bit of text in an image) that computers were supposedly incapable of solving but humans were.

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1answer
56 views

How can I protect my website if services like 2Captcha claim to crack the new reCAPTCHA?

Have recently seen their ad where they claim to be able to do it due to the fact that unlike most OCR CAPTCHA crackers which are bots, they use workforce, humans behind the scenes. Although I still ...
0
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2answers
56 views

How do I secure my site against human spam farm attacks?

I have a Q&A site that has recently been attacked by what I strongly believe to be a human spam farm, as described in these articles: Spammers Pay Others to Answer Security Tests Are You Human? ...
2
votes
1answer
124 views

Why do “Registration-bots” exist? What do they gain from registering on my site?

I'm curious as i've been developing some anti-bot procedures for a website, only because I see others doing it. But Why?. What do the bots gain from registering hundereds of accounts? I'm building an ...
2
votes
5answers
424 views

Chinese bots in my forum

I have a small community forum that doesn't really get posts or any real traffic. The only thing that happens on the regular is bots with Chinese IPs signing up gibberish usernames. Most bots don't ...
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1answer
39 views

Whats the name of this captcha software? [closed]

I'm looking for an anti-bot software to prevent the content copy on our sites. I have found that some other webs are using a captcha program, here is a pic: ...
1
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2answers
423 views

How secure is a static CAPTCHA?

I have seen some webmasters using a CAPTCHA that doesn't change at all. And many of them use JavaScript to validate these value. For example: if(captchaCode != "4ERJZ") Since most of the web ...
0
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1answer
713 views

Apache real time robot detection

Background Our website is being a. scraped - complete pages downloaded b. spidered - complete pages and sub links followed c. mined - specific files downloaded at high speed by hundreds of ...
2
votes
2answers
454 views

Does anyone run a site with Pligg? What is the most effective way to stop spam sign ups? [duplicate]

Possible Duplicate: How can I prevent spam on sites which I control? Specifically trying to combat things like this! http://www.autopliggdotcom (didnt want to give them a link!)
0
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1answer
198 views

Spammers in my Magento blog comment section! [duplicate]

Possible Duplicate: How can I prevent spam on sites which I control? I have a blog extension installed on my Magento website. But I regularly receive spam comments on the blog. To help ...
2
votes
1answer
514 views

What Captcha Services are available for free?

I'm looking for a free captcha service for a html/css/php site. reCAPTCHA seems to be very famous. Is it effective? Are there maybe other good captcha services which are available for free?
7
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1answer
441 views

Self hosting of recaptcha-like system to digitise my uploaded books

From wikipedia reCAPTCHA is a system ... that uses CAPTCHA to help digitize the text of books while protecting websites from bots I have a lot of scanned documents that I'd like to convert, ...
3
votes
4answers
264 views

Removing CAPTCHA is harmful for my forms?

I have some services on my site that developed by PHP , it seems having CAPTCHA in my registration form is decreasing registering users , I tend to remove CAPTCHA at least on my registering form , is ...
17
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7answers
3k views

Is reCaptcha now basically useless?

Is reCaptcha now basically useless? I have read around the internet that reCaptcha has been broken, and spam bots easily overcome it. Has Google addressed this at all. Do they have any plans to fix ...
2
votes
4answers
305 views

Is it good idea to put a captcha on credit card payment form

Is it good idea to put a captcha on credit card payment form? I am thinking to put one on my asp.net mvc application's payment section to make it more secure but I have never seen anybody doing ...
2
votes
1answer
149 views

Chinese CAPTCHAs

I need to implement a CAPTCHA for a Chinese (Simplified) website. Does anyone know how CAPTCHAs are normally presented on Chinese sites? I have seen some which just display standard decimal numbers ...
2
votes
2answers
1k views

Which languages are supported by reCAPTCHA?

The documentation states that "Any supported language code." is supported, but then says: Which language is used in the interface for the pre-defined themes. The following languages are supported: ...
2
votes
2answers
114 views

Why are captcha fields so prevelant across the internet?

Seems to me that they are an easy way out and band aid solution to a problem that could be solved in other ways. I have never implemented a captcha field on a website and do not intend to in the ...
3
votes
1answer
207 views

Recaptcha statistics

Of late recaptcha images have become excessively difficult to decipher. Is there any way to get analytics on unsuccessful attempts before a successful one for your website? I'm pretty certain the ...
5
votes
3answers
1k views

How to tell whether spammers are bots or humans?

How can you tell if the people that are spamming your forum or website are in fact bots or human spammers? Please note that the question is not about preventing spammers. It is to determine if the ...
2
votes
2answers
117 views

Strange spam posts not making sense [duplicate]

Possible Duplicate: What kind of spam is this? I'm running a web site with a forum where one small part is open for posting from unregistered users. The site uses captcha, but still some ...
1
vote
1answer
64 views

Problematic using Captcha on billing page

I have simple captcha on user page. I want make it refresh if user input incorrect captcha, I just wanna ask Should I do it or I just add a simple button to refresh it.
2
votes
2answers
764 views

Has anybody earned $0.25+ from each of a captcha (on your website) passing?

I am a real dummy in web monetizing schemes. [ 1 ] informs that a captcha vendor: "charges a fee of about 25 cents to 50 cents for each form that is filled out using a Type-In ad [captcha]... ...
3
votes
2answers
278 views

Localized CAPTCHA

What are effective CAPTCHA solutions that can have localized description, and CAPTCHA text itself is either language-neutral, or can be localized (for Polish language)? It is to be used to protect a ...
15
votes
8answers
428 views

Effective captcha solutions [duplicate]

Possible Duplicate: How can I prevent spam on sites which I control? ReCaptcha is all the rage at the moment, Based on customer/user feedback, what other captcha or general human ...