Miscellaneous Hacks - Enhanced Captcha Image Verification - stop bots from signing up!!

Title : Enhanced Captcha Image Verification

Version : 1.1

Coder : Andy Calderbank & Jason Williams

Purpose : Add extra Image Verification to the registration process, using an alternative system to the Captcha system.

Why : It would appear that spammers can now "read" the Captcha codes and overcome the verification process.

How : This extra feature uses images which are harder for a spam program/bot to interpret than text characters. The user has a choice of 4 randomly displayed images, and the answer is given below. The user must click on that image to proceed, if the incorrect image is selected an error message is shown. The images are randomly shown (from however many are in the directory - you can have as many as you want, just has to be more that 4!) and are automatically created from the images/verification/ directory - all on the fly. Sample images are included with this release, but you can use your own - I recommend using 100 x 100 pixels, in .jpg format and naming the image with a meaningful title (ie A House.jpg) - the extension is stripped so only the filename itself is shown.

To further enhance security, the images are passed through a script which means that none of the images on the screen have file names - and cannot be associated to the question by title alone.

I have been testing this on my forum and have found it to be effective - I cannot guarantee that this will stop all spamming, but this relies more on human input than a computer "reading" the image.

Important : This has been tested on 3.6.2 - I cannot guarantee it will work on anything above, please test with caution - and as always BACKUP FIRST! This will not work on anything below 3.6.0.

Demo : http://www.steadiforum.com/register.php

I hope this is help to the VBulletin community as I know this is a growing problem. I don't fancy the thought of trawling through hundreds of new members deleting stupid usernames and spam posts.

Installation :

1. Upload the verification/ directory to your images/ folder - make sure .htaccess and show.php are present - otherwise it won't work.
2. Import Product - product-image_verification.xml

Upgrading :

1. Upload show.php to the images/verification/ directory.
2. Import Product - product-image_verification.xml - select Allow Overwrite to enable upgrade.

Requirements : GD Libraries installed

File uploads : 39 (including images)
Files to Import : 1
New Templates : 1
New Phrases : 5
Uses Hooks : 1
New Queries : 0

History :
v1.0 - Original release
v1.01 - Slight code change for forums in sub-directories (thanks go to Barakat for solving this one)
v1.1 - Issue resolved with Windows servers also template clean up for xhtml compliance
v1.11 - Added version check function, minor upgrade.

Done - if you like please click install! (and I won't ask for any donations as long as you click Nominate for MOTM!)

Don't forget you don't have to use the provided images - you can customise these to any you wish - I've used ones that are hopefully universal and everyone will recognise.

[Robru]

Works like a charm with 3.6.4, thanks

[tazping2000]

Sometimes it asks to click a picture, but although the four pics are there, the one it asks you to click is not. Is this correct?

Apart from that it all works fine on 3.6.3 (Apache).

With regard to some folk getting a red 'X' instead of a pick, I got that first, and solved it by just closing the browser, and opening a new one.

[steadicamop]

Originally Posted by beishe8

Sad... I cannot upload .htaccess (The dot is the problem with my host)

It shouldn't be too much of an issue, don't worry about uploading it, create an empty index.html file and upload that, then change the code in show.php:

Change:

PHP Code:

&& $entry != '.htaccess' 


To:

PHP Code:

&& $entry != 'index.html' 


You will also need to edit the plugin - don't worry it's quite easy:

AdminCP -> Plugins & Products -> Plugin Manager -> Extra user verification

Click edit and find:

PHP Code:

&& $entry != '.htaccess' 


and change to:

PHP Code:

&& $entry != 'index.html' 


Click save then check that the verification still works - this should not affect how the product works.

Then you should be good to go - all this does is stop the directory from being listed.

Jason

[steadicamop]

Originally Posted by tazping2000

Sometimes it asks to click a picture, but although the four pics are there, the one it asks you to click is not. Is this correct?

Apart from that it all works fine on 3.6.3 (Apache).

With regard to some folk getting a red 'X' instead of a pick, I got that first, and solved it by just closing the browser, and opening a new one.

Does the answer ever say "thumb"? If so then re-upload the product from the new package - if you use Windows to look inside the directory with the images in it creates a Thumbs.db file - a typo early on meant it was looking for thumbs.db and not Thumbs.db - version 1.1 has fixed this. If you still have problems PM me your forum link and I will take a look for you.

Jason

[tazping2000]

Does the answer ever say "thumb"?

No, I just installed 1.1 for the first time.

I'll have a fiddle later, need to go out now. Thanks.

[jmke]

Installed and working fine,

http://www.madshrimps.be/vbulletin/register.php

thanks a lot for this!

[steadicamop]

Looking good - you know you don't have to use _ between words, just name the file and include spaces, the script reads the files as they are and displays the answer as shown in the filename.

[guvner]

Great hack - thank you very much - working well on 3.6.3 (patched to .4)

Once question - how would I be able to make the image phrase bold - i.e.

Bart Simpson instead of Bart Simpson - can't find the phrases anywhere so I'm guessing your script draws them from the image title?

Mike

[beishe8]

Originally Posted by steadicamop

Then you should be good to go - all this does is stop the directory from being listed.

Thanks Jason !

[steadicamop]

Originally Posted by guvner

Great hack - thank you very much - working well on 3.6.3 (patched to .4)

Once question - how would I be able to make the image phrase bold - i.e.

Bart Simpson instead of Bart Simpson - can't find the phrases anywhere so I'm guessing your script draws them from the image title?

Mike

This will sort that -

AdminCP -> Styles & Templates -> Style Manager -> [the style you use] -> Edit Templates

Find the image_verification template and open that, look for this code

PHP Code:

$vbphrase[click_image] $question 


and replace with this

PHP Code:

$vbphrase[click_image] <strong>$question</strong> 


I just tried that out and it works fine for me.

HTH

Jason