captcha

How to protect html form from spammers?

Update: The answer was accepted because I recommended KeyCAPTCHA. From my hard-earned painful expereince, KeyCAPTCHA is a scam by professional spammers. I removed my recommendations of KeyCAPTCHA Note that most professional spambots are integrated with sweatshops (1 USD a 1000 solutions) human captcha solvers API. When a spambot cannot pass captcha itself it (spam bot), … Read more

Recommendations for java captcha libraries [closed]

I am the author of SimpleCaptcha. While I would recommend — for humanity’s sake — using ReCaptcha where you can, I provided SimpleCaptcha because some organizations have policies which prohibit libraries like ReCaptcha. SimpleCaptcha is meant to be entirely stand-alone, with no external dependencies: as long as you are in a J2EE container, you should … Read more

How to Prevent SPAM without CAPTCHAs or a Centrally managed system (e.g. akismet)

I basically use one trick on my site to prevent Spam and it works great (at least until spambot programmers will read this post 😉 ). Code is like this: In the script that builds the site which contains the form, I implemented: $_SESSION[‘lastSiteId’] = ‘something Unique’; $_SESSION[‘lastSiteRequest’] = time(); The script that contains the … Read more

How does Google reCAPTCHA v2 work behind the scenes?

This is speculation, but based on Google’s reference to the “risk analysis engine” they use (http://googleonlinesecurity.blogspot.com/2014/12/are-you-robot-introducing-no-captcha.html) I would assume it looks at how you behaved prior to clicking, how your cursor moved on its way to the check (organic path/acceleration), which part of the checkbox was clicked (random places, or dead on center every time), … Read more

Selenium app redirect to Cloudflare page when hosted on Heroku

In case the Selenium driven ChromeDriver initiated google-chrome Browsing Context is getting redirected to the page… … this implies that a Cloudflare program is blocking your program from accessing the AUT (Application under Test). Analysis There can be several reasons behind Cloudflare blocking the access as follows: Cloudflare have idenified your program asa bot and … Read more

Is there any possible ways to bypass cloudflare security checks?

When you visit a site which is protected by cloudflare, it would contain a security check which you cannot bypass and on failing eventually your access is denied and you are redirected to the captcha challenge page due to the requests from low reputation IP addresses. IP Reputation is calculated based on Project Honeypot, external … Read more