2005
09.16

Captcha! Plugin

Warning! CAPTCHA! is DISABLED on this site.
Even though this plugin is still maitained, I’m using another one. Read why.

You can also go to the phorum for help.

I wanted my WordPress to have one of those nice Captchas challenges to avoid spam.

There are already some of them, but I found them not suitable for my webhosting service (Secureimage), or a bit weak (Trencaspammer). So I started my own based on the HN Captcha PHP class. To see a demo of this plugin just try to enter a comment on the main page (Okay, still in Spanish. Bilingual web soon to come).

Needs the GD library class, a Javascript compatible browser and TrueType fonts in a server folder to work. You can download some of TTF (TrueType) fonts for free from Dafont. The more artistic the font, the better the challenge will be.
The plugin allows to request another challenge if the current one is illegible.

Hope you enjoy it.

[Download] Current version of Captcha! plugin

Changelog:

  • Version 2.6
    Bugfix: Fixed a security bug against CSRF and XSS
    Bugfix: Prevents the code length to be lower than one char.
  • Version 2.5d
    +Feature: Enhaced GDLib version detection (does not require phpinfo() function).
  • Version 2.5c
    Bugfix: Fixed a bug which prevented some effect options (sinewave, B&W) to be updated correctly. Thanks Hugo!.
  • Version 2.5b
    Bugfix: Fixing bad javascript rendering bug. Thanks, Gidion!.
  • Version 2.5a
    Bugfix: Stupid bug. Captcha 2.5 was allowing comments. Grrrr.
  • Version 2.5
    Bugfix: Captcha 2.x seemed to be filtering pingbacks. Fixed.
  • Version 2.4
    Feature: Checks for the availability of ImageFilter function (PHP >= 5.0)
    Feature: Checks for the availability of Iconv.
  • Version 2.3
    Feature: Added Anchor so every try the page jumps directly to captcha input.
    Feature: Cleaner code.
    Feature: Sine wave color-flag (optional), only color and Black & White optional mode.
    Feature: Can choose number of max tries.
  • Version 2.2
    Bugfix: Captcha didn’t delete spam comments in WP 1.5. Fixed.
  • Version 2.1
    Bugfix: Fixed a bug in the refresh button.
    Feature: Added senoidal image distortion.
    Feature: Deletes guessed keys.
  • Version 2.0
    Feature: Danish translation of captcha! (Thanks, Ulrik Nielsen)
    Feature: Portuguese (Brazil) translation of captcha! (Thanks, Francis Augusto Medeiros)
    Feature: One single file! Captcha is now one single compact file. Source code is much cleaner and neat (for future versions, however, CSS and languaje files will be apart).
    Feature: Images generated on the fly. TMP/ cache images no longer needed (and no more “Garbage error”
    Feature: Now Captcha! remembers previous state, so a user is given several tries (3 by default) to guess it before changing to a new code. The code look is different each time, even if the same code is required (improved security).
    Feature: Improved security. Real public key not shown, so it makes really difficult to guess the sequence via a bot.
    Feature: Random pattern background and code colors added => Greater security.
    Feature: Annoying javascript popup (when bad code entered) has been removed: Now the user will be asked to reenter the code in the captcha form.
    Bugfix: Some servers have permalinks broken, so entering a bad captcha returned to the main page, losing comment content. This should be fixed now.

See Changelog for previous versions ▼

Some sites using (or which used ;)) this captcha:

[Uniform Server] [stefanrusche.de] [A Dose of Geekish Sanity] [Markus' Blog] [Silke Thoss] [scudly.com] [AAWakenings] [bdk… the man, the myth, the whatever…] [ElectroLund] [Pedja] [Outlandish Josh] [macslow.mine.nu] [Zoomer v2.0] [The BullPen Blog] [me blog] [Natalie Gulbis - Sport Memorabilia] [Bitte keine heiße Asche einwerfen] [Daniel Lemire’s blog] [Ido’s Blog] [Onderonsjes] [schimana.net] [Hillsidelounge] [MLL's web site] [Axel Segebrecht] [Normadicoder] [Laitsas’ Penguinblog]

Share
  1. [...] contact form. To avoid Spam, I use reCaptcha which is a very good Captcha system (even better than the one I used for the blog comments). You can see it in action in the contact form of this [...]

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  2. [...] El Rinc n de Boriel Captcha! PluginRecent Comments. Boriel: El Tratado de Lisboa (que es la Constituci n Europea con otro nombre, Boriel: Hola, Francisco: Gracias por tus felicitaciones. [...]

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  3. [...] para proteger vuestro wordpress. En lo que a soluciones anti-spam se refiere, probad CAPTCHA. http://www.boriel.com/?page_id=17 y  WordPress Hashcash 3.2 http://elliottback.com/wp/archives/2005/10/23/wordpress-hashcash-30-beta [...]

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  4. [...] recently received an email asking me to fix some Captcha! vulnerabilities that will allow spammers to enter automated spam comments. Such supposed [...]

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  5. [...] Captcha plugin potrebbe essere una soluzione migliore, ma purtroppo gi capitato che gente rinunci a postare un [...]

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  6. [...] Captcha!: Muestra una imagen con un código alfanumérico que el visitante debe introducir para que su [...]

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  7. [...] Visit & Download [...]

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  10. [...] Captcha! Pluggin [...]

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  11. [...] que al final he incorporado un captcha de toda la vida. Concretamente me he decidido por el plugin CaptCha!. De momento lo tengo configurado para ser un captcha sencillo, sin distorsión en la imagen, etc. [...]

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  12. [...] Скачать плагин можно здесь [...]

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  13. [...] http://www.boriel.com/?page_id=17 [...]

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  14. [...] dans les commentaires du blog depuis hier, j’ai décidé de mettre en place le plugin “Captcha!” pour WordPress. Ce plugin ajoute (comme son nom l’indique) un captcha sur le [...]

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  15. [...] 今回導入したのはCapcha!と呼ばれるプラグインです。 [...]

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  16. [...] y no demasiado engorrosa y al final me decidí, de entre todas las que se ofrecen, por un sistema Captcha (el típico “Introduce este código en la ventana”), pero tras leer las explicaciones [...]

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  17. [...] Captcha! [...]

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  18. [...] 这里是一个Wordpress的Captcha插件:http://www.boriel.com/?page_id=17 [...]

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  19. [...] El Rincón de Boriel » Captcha! Plugin When I turn off Captcha, WP displays fine, including the footer of the page. When I turn Captcha on, the page abruptly ends and does not display the footer area of WP which should include the Captcha … http://www.boriel.com/plugins/captcha-plugin/ [...]

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  20. [...] Repositório anti-spam: http://codex.wordpress.org/Plugins/Spam_Tools O que eu usei:  http://www.boriel.com/?page_id=17 [...]

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  21. [...] 留言的時候,加入字碼認證,這方法和 (4) 一樣麻煩,看錯打錯是常有的事,如果你用的是網上下載的流行字型,很容易被 spammer 破解,除非你願意自己設計字型。 [...]

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  22. [...] Maggiori info [...]

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  23. [...] ora ho risolto solo il secondo punto, ho installato il captcha! plugin che ho diligentemente modificato per supportare anche la lingua italiana. D’ora in poi per [...]

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  24. [...] Captcha!: Muestra una imagen distorsionada (’captcha’) con un código alfanumérico que el usuario debe introducir para que su comentario sea aceptado (se usa contra el Spam). [...]

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  25. [...] die if you saw how many links these spam programs try to include! alas, i stumbled upon captcha, a program that requires anyone who wishes to leave a comment to type in the letters & numbers [...]

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  26. [...] : Captcha要求留言者须首先回答一个简单问题,如 [...]

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  27. [...] Website El Rincón de Boriel (Captcha! Plugin) [...]

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  28. [...] Captcha!: Muestra una imagen distorsionada (’captcha’) con un código alfanumérico que el usuario debe introducir para que su comentario sea aceptado (se usa contra el Spam). [...]

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  29. [...] Visit [...]

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  30. [...] CaptCha! – im Moment inaktiv, siehe hier [...]

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  31. [...] the Spam Tools page that listed 8 plugins under Captcha. I decided to start with the one called Captcha! BUT…when I clicked on its link I landed on a website sporting a vintage Sinclair ZX Spectrum [...]

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  32. [...] I clicked on its link I landed on a website sporting a vintage Sinclair ZX Spectrum ( <3 ) [...]

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  33. [...] to the new server I thought it was time to re-evalute this decision and looked at alternatives to Captcha! The author of this plug-in has stopped supporting it / using it and has moved over to one called [...]

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