WordPress WooCommerce SagePay Direct Payment Gateway plugin XSS Vulnerability

Summary
This host is installed with Wordpress WooCommerce SagePay Direct Payment Gateway Plugin and is prone to cross site scripting vulnerability.
Impact
Successful exploitation will allow attacker to execute arbitrary HTML and script code in a user's browser session in the context of an affected site. Impact Level: Application
Solution
Upgrade to WordPress WooCommerce SagePay Direct Payment Gateway plugin version 0.1.6.7 or later. For updates refer to http://wordpress.org/plugins/sagepay-direct-for-woocommerce-payment-gateway
Insight
Input passed via the 'MD' and 'PARes' parameters to pages/3DComplete.php script is not properly sanitised before being returned to the user.
Affected
WordPress WooCommerce SagePay Direct Payment Gateway plugin before version 0.1.6.7.
Detection
Send a crafted data via HTTP GET request and check whether it is able to read cookie or not.
References