SS-2017-001: XSS In page name (and a question)

[Patrick Nelson]

I noticed a low severity vulnerability was posted in our security releases page here:

https://www.silverstripe.org/download/security-releases/ss-2017-001/

I'm having trouble understanding the description. Could someone please provide a more detailed explanation, or better, a PoC for this as well as a context? I presume this requires CMS access.