The Cakephp 3.x implementation of the following captcha http://www.ejeliot.com/pages/2

installation should be done by composer

composer require hashmode/cakephp-captcha:~1.0 

Load from bootstrap

Plugin::load('CakephpCaptcha'); 

Load component in your controller's initialize function by

$this->loadComponent('CakephpCaptcha.Captcha'); 

Add some function in your controller to call from view

public function image() { $this->autoRender = false; echo $this->Captcha->image(5);	} 

From view

<img src="<?php echo $this->Url->build('/users/image');?>" /> 

You can concatenate some random chars by js to the url if the users refresh the captcha - to prevent cache-related issues

To check if the provided value is correct

$this->Captcha->check($userSubmittedData)