GHSA-gwcr-j4wh-j3cq Jetty Utility Servlets ConcatServlet Double Decoding Information Disclosure Vulnerability

• Maven org.eclipse.jetty:jetty-servlets: < 9.4.41 → fixed in 9.4.41 • Maven org.eclipse.jetty:jetty-servlets: >= 10.0.0, < 10.0.3 → fixed in 10.0.3 • Maven org.eclipse.jetty:jetty-servlets: >= 11.0.0, < 11.0.3 → fixed in 11.0.3

Requests to the `ConcatServlet` and `WelcomeFilter` are able to access protected resources within the `WEB-INF` directory. For example a request to the `ConcatServlet` with a URI of `/concat?/%2557EB-INF/web.xml` can retrieve the web.xml file. This can reveal sensitive information regarding the implementation of a web application. This occurs because both `ConcatServlet` and `WelcomeFilter` decode the supplied path to verify it is not within the `WEB-INF` or `META-INF` directories. It then uses this decoded path to call `RequestDispatcher` which will also do decoding of the path. This double decoding allows paths with a doubly encoded `WEB-INF` to bypass this security check. Impact This affects all versions of `ConcatServlet` and `WelcomeFilter` in versions before 9.4.41, 10.0.3 and 11.0.3. Workarounds If you cannot update to the latest version of Jetty, you can instead deploy your own version of the `ConcatServlet` and/or the `WelcomeFilter` by using the code from the latest version of Jetty.