Overview   XML documents optionally contain a Document Type Definition (DTD), which, among other features, enables the definition of XML entities. It is possible to define an entity by providing a substitution string in the form of a URI. Once the content of the URI is read, it is fed back into the application that is processing the XML. This application may echo back the data (e.g. in an error message), thereby exposing the file contents. (CWE-611)   Description   Hitachi Vantara Pentaho Business Analytics Server versions before 10.2.0.2, including 9.3.x and 8.3.x, do not correctly protect Pentaho Data Integration MessageSourceCrawler against out-of-band XML External Entity Reference.   Impact   By submitting an XML file that defines an external entity with a file:// URI, an attacker can cause the processing application to read the contents of a local file. Using URIs with other schemes such as http://, the attacker can force the application to make outgoing requests to servers that the attacker cannot reach directly, which can be used to bypass firewall restrictions or hide the source of attacks such as port scanning.