cPanel 10 handle.html XSS Vulnerability

mime/handle.html (usually https://www.example.com/cpanel/frontend/x/mime/handle.html) of cPanel 10 is
vulnerable to an XSS vulnerability. This can be leveraged by entering an injected html into the extension
and/or mime-type specified. I sucesfully leveraged this issue causing the page to execute the code
<script>alert('hi')</script> each time. I also got it to properly display an image with the img-src tag.
This is semipermanent because it stays on the page after the URL is left.