Recently our support department received a mail from a client regarding receiving spam through an on-line form on their website and we thought it deserves a mention as others may be experiencing similar issues  My first thoughts were how easy it actually is to code a small script to submit a form bringing back memories of coding similar scripts back in 2003.

Of course Captcha followed and more and more sites added Captcha to there on-line forms and the issue appeared to be resolved.  Now there’s more and more published cracks of Captcha code and the issue returns.  Our response to our client was the following potential solutions:

1. Generate the form through Javascript which will prevent scripts and non browser users from viewing the form.  Down side is reduced accessibility.
2. The receiving script should validate the form was sent from your website using a combination of MD5 hash + date.  Down side some intelligent scripts may process the form on your website to bypass.
3. Use a captcha to ensure users need to enter graphic code to submit the form.  Down side captcha is becoming easier to crack through code.
4. Add a script that will time the form completion to identify robots or human completion.  Down side some visitors may use auto-complete resulting in false positives.

Not an extensive list more of ideas to reduce spam through the form and I will discuss this with our coders to see if we could publish some code that helps reduce spam through FORM’s.