GHSA-QJ4X-9G63-25G6 XWiki Platform Old Core: Resource path traversal via /skin/ action endpoint in Jetty 12+

Impact With Jetty 12+ a user can craft a URL to access any resource the Jetty instance is allowed to access. For example http://host/xwiki/bin/skin/..%252f/..%252f..%252f..%252f..%252f..%252f..%252f..%252fetc/passwd allows downloading the content of the /etc/passwd file, provided Jetty is allowed...