XWiki Platform vulnerable to reflected cross-site scripting via back and xcontinue parameters in resubmit template

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. Users are able to forge an URL with a payload allowing to inject Javascript in the page (XSS). It's possible to exploit the resubmit template to perform a XSS, e.g. by using URL such as: > xwiki/bin/view/XWiki/Main xpage=resubmit&resubmit=javascript:alert(document.domain)&xback=javascript:alert(document.domain). This vulnerability exists since XWiki 2.5-milestone-2. The vulnerability has been patched in XWiki 14.10.5 and 15.1-rc-1.