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100%
10-16-2007, 06:13 PM
soon terminated?

Preventing SPAM without using a CAPTCHA

Concept:
For people who don’t know this trick already, here is how you do it:

1. Add an input field to your form, with some interesting name, for example ‘URL’.
<input name="url" type="text" value=""/>
2. Hide the input box using css so that users(genuine) cannot see it directly.
<style>
.style1 {
display: none;
}
</style>
<p class="style1"><input name="url" type="text" value=""/></p>
3. While processing the form check if the “url” contains any value. If it does, reject the post or put it for moderation.
if (strlen(trim($_POST['url'])) > 0){
//It is a spam, reject this post here
}

tesco
10-16-2007, 09:21 PM
soon terminated?

Preventing SPAM without using a CAPTCHA

Concept:
For people who don’t know this trick already, here is how you do it:

1. Add an input field to your form, with some interesting name, for example ‘URL’.
<input name="url" type="text" value=""/>
2. Hide the input box using css so that users(genuine) cannot see it directly.
<style>
.style1 {
display: none;
}
</style>
<p class="style1"><input name="url" type="text" value=""/></p>
3. While processing the form check if the “url” contains any value. If it does, reject the post or put it for moderation.
if (strlen(trim($_POST['url'])) > 0){
//It is a spam, reject this post here
}And what would that do?:blink:

100%
10-16-2007, 09:27 PM
i have no clue, other than maybe remove captcha?
:hope:

tesco
10-16-2007, 09:37 PM
i have no clue, other than maybe remove captcha?
:hope:
:lol:

The way I see it is that would never catch anyone because nobody is entering any text into that field.
Do they think a bot/computer would do it?:huh:

RealitY
10-17-2007, 06:03 AM
Think thats the point although thats not why we have it...

Barbarossa
10-17-2007, 09:34 AM
I think it is assuming that a bot would detect the hidden input field and feel duty-bound to populate it with something :idunno:

100%
10-17-2007, 09:41 AM
source - http://digg.com/programming/Preventing_SPAM_without_using_a_CAPTCHA

Snee
10-17-2007, 05:18 PM
I think it is assuming that a bot would detect the hidden input field and feel duty-bound to populate it with something :idunno:

Or lyke fill in in that field instead of the proper one, if the field in wot you lyke properly post your posts is the child behind it :idunno:

Depending on the bot it might also be possible that changing the field's title- or name-attribute to what you normally call the proper input field might make the bot post innit.


Dunno, rly, I've never picked any apart, but I think things could work that way.

peat moss
10-18-2007, 02:48 AM
Its so easy a five year old child could figure it out . Quick somebody fetch a five year old ......

Barbarossa
10-18-2007, 12:29 PM
I think it is assuming that a bot would detect the hidden input field and feel duty-bound to populate it with something :idunno:

Or lyke fill in in that field instead of the proper one, if the field in wot you lyke properly post your posts is the child behind it :idunno:

Depending on the bot it might also be possible that changing the field's title- or name-attribute to what you normally call the proper input field might make the bot post innit.


Dunno, rly, I've never picked any apart, but I think things could work that way.

I actually liked the suggestion inside the discussion thread, to have a hidden field and populate it using the javascript on the page. Bots or spiders don't tend to run the javascript on the page, so all you do is ignore the request unless the field is filled in as expected.

I've put that into our corporate "contact us" page, cos we get a few empty submissions from bots/spiders for some reason :idunno:

tesco
10-20-2007, 03:46 PM
CAPTCHA is turned off now.
We will see how this goes. If the same problem that we had before comes back then CAPTCHA will return.

It's a shame. So much GENIOUS work went into creating that CAPTCHA plugin, now it's gonna get no use. :no:
Oh well :lol:

100%
10-20-2007, 03:50 PM
AAAaaaaaaaaaaaaaaaaaaaaaaahhhhh thank you, mr.Genious.