Spring Security Advisories

It was identified that Spring MVC processed user provided XML with JAXB in combination with a StAX XMLInputFactory without disabling external entity resolution. External entity resolution has been disabled in this case. It was subsequently discovered that this fix was incomplete (CVE-2013-6429, CVE-2014-0054).

The Spring OXM wrapper did not expose any property for disabling entity resolution when using the JAXB unmarshaller. There are four possible source implementations passed to the unmarshaller: DOMSource, StAXSource, SAXSource and StreamSource.

For a DOMSource, the XML has already been parsed by user code and that code is responsible for protecting against XXE.

For a StAXSource, the XMLStreamReader has already been created by user code and that code is responsible for protecting against XXE.

For SAXSource and StreamSource instances, Spring processed external entities by default thereby creating this vulnerability.

The issue was resolved by disabling external entity processing by default and adding an option to enable it for those users that need to use this feature when processing XML from a trusted source.