numero = 103481
interpreted = N
texte = Nice Ken :) And for those looking for other methods .... http://dev.idfk.com.au/captcha/ I would love to do one with Imagemagick (http://www.imagemagick.org), when I get around to it I will post the code. Regards Stuart Tremain IDFK Web Developments AUSTRALIA webdna@idfk.com.au On 26/08/2009, at 12:43 AM, Kenneth Grome wrote: > Do hackers these days use scripts that: > > 1- read the content of a web page > 2- extract strings like "two hundred eighty three" > 3- convert them into numbers like "283" > 4- enter these values into blank form fields > > ... so they can get past text-based captcha systems designed to > prevent forms from being submitted by hackers? > > Sincerely, > Ken Grome > > > > P.S. I'm giving the code away free but I don't think file > attachments are allowed in this talk list so you'll have to get it > from my website. Please do not redistribute this file without my > permission, thanks: > > http://kengrome.com/downloads/captcha.tpl.zip > > Here's my description so you can figure out if it's worth > downloading *before* you download: > > This captcha.tpl page creates a word-based captcha system entirely > in webdna with no cookies or database required. It displays a 6- > digit number as words. To answer the captcha challenge correctly the > visitor must translate this value into corresponding numeric digits. > > Here's how to use this file: > > 1- Place this captcha.tpl file somewhere inside your web folder > hierarchy > > 2- Place an [include /path/to/captcha.tpl] tag at the top of the > form page you want to protect > > 3- Insert this hidden form field into the form: name=captchaLookup value=[captchaLookup]> > > 4- Insert this text input field into the form: name=captchaAnswer> > > 5- Place the [captchaWords] tag on the page wherever you want the > "number-as-words" text to appear > > The first part of the system is done, now let's proceed with the > second part. Use these showif's on the page that receives the form > post to determine whether or not the visitor typed the correct > answer to the captchaAnswer field, then change what's inside the > showif's to show the proper code based on the visitor's captcha > answer: > > [code removed for clarity in this email] > > When you uncomment the following webdna comment section > you can test this captcha system entirely within this file > before installing it in your website: > > [code removed for clarity in this email]
Associated Messages, from the most recent to the oldest:
Nice Ken :) And for those looking for other methods .... http://dev.idfk.com.au/captcha/ I would love to do one with Imagemagick (http://www.imagemagick.org), when I get around to it I will post the code. Regards Stuart Tremain IDFK Web Developments AUSTRALIA webdna@idfk.com.au On 26/08/2009, at 12:43 AM, Kenneth Grome wrote: > Do hackers these days use scripts that: > > 1- read the content of a web page > 2- extract strings like "two hundred eighty three" > 3- convert them into numbers like "283" > 4- enter these values into blank form fields > > ... so they can get past text-based captcha systems designed to > prevent forms from being submitted by hackers? > > Sincerely, > Ken Grome > > > > P.S. I'm giving the code away free but I don't think file > attachments are allowed in this Talk List so you'll have to get it > from my website. Please do not redistribute this file without my > permission, thanks: > > http://kengrome.com/downloads/captcha.tpl.zip > > Here's my description so you can figure out if it's worth > downloading *before* you download: > > This captcha.tpl page creates a word-based captcha system entirely > in webdna with no cookies or database required. It displays a 6- > digit number as words. To answer the captcha challenge correctly the > visitor must translate this value into corresponding numeric digits. > > Here's how to use this file: > > 1- Place this captcha.tpl file somewhere inside your web folder > hierarchy > > 2- Place an [include /path/to/captcha.tpl] tag at the top of the > form page you want to protect > > 3- Insert this hidden form field into the form: name=captchaLookup value=[captchaLookup]> > > 4- Insert this text input field into the form: name=captchaAnswer> > > 5- Place the [captchaWords] tag on the page wherever you want the > "number-as-words" text to appear > > The first part of the system is done, now let's proceed with the > second part. Use these showif's on the page that receives the form > post to determine whether or not the visitor typed the correct > answer to the captchaAnswer field, then change what's inside the > showif's to show the proper code based on the visitor's captcha > answer: > > [code removed for clarity in this email] > > When you uncomment the following webdna comment section > you can test this captcha system entirely within this file > before installing it in your website: > > [code removed for clarity in this email]
Stuart Tremain
The WebDNA community talk-list is the best place to get some help: several hundred extremely proficient programmers with an excellent knowledge of WebDNA and an excellent spirit will deliver all the tips and tricks you can imagine...