YITH WooCommerce Compare WordPress Plugin unauthenticated PHP Object injection vulnerability

Abstract

A PHP Object injection vulnerability was found in the YITH WooCommerce Compare WordPress Plugin, which can be used by an unauthenticated user to instantiate arbitrary PHP Objects. Using this vulnerability it is possible to execute arbitrary PHP code.

OVE ID

OVE-20160803-0006

Tested versions

This issue was successfully tested on the YITH WooCommerce Compare WordPress Plugin version 2.0.9.

Fix

This issue is resolved in YITH WooCommerce Compare version 2.1.0.

Introduction

The YITH WooCommerce Compare WordPress Plugin is an extension of WooCommerce plugin that allow your users to compare some products of your shop. A PHP Object injection vulnerability was found in the YITH WooCommerce Compare WordPress Plugin, which can be used by an unauthenticated user to instantiate arbitrary PHP Objects.

Details

This issue is possible due to an unsafe call to unserialize() in the __construct() method. The input is taken directly from the yith_woocompare_list cookie as can be seen in the following code fragment:

includes/class.yith-woocompare-frontend.php:

/**
	 * Constructor
	 *
	 * @return YITH_Woocompare_Frontend
	 * @since 1.0.0
	 */
	public function __construct() {
	
		// set coookiename
		if ( is_multisite() ) $this->cookie_name .= '_' . get_current_blog_id();
	
		// populate the list of products
		$this->products_list = isset( $_COOKIE[ $this->cookie_name ] ) ? json_decode( maybe_unserialize( $_COOKIE[ $this->cookie_name ] ) ) : array();

It has been confirmed that this issues can be used to execute arbitrary PHP code.