Security Information / 2014 / Security Information -- DSA-2842-1 libspring-java

Debian Security Advisory

DSA-2842-1 libspring-java -- denial of service

Date Reported:

13 Jan 2014

Affected Packages:

libspring-java

Vulnerable:

Yes

Security database references:

In the Debian bugtracking system: Bug 720902.
In Mitre's CVE dictionary: CVE-2013-4152.

More information:

Alvaro Munoz discovered a XML External Entity (XXE) injection in the Spring Framework which can be used for conducting CSRF and DoS attacks on other sites.

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
• 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.

It was also 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.

For the stable distribution (wheezy), this problem has been fixed in version 3.0.6.RELEASE-6+deb7u1.

For the unstable distribution (sid), this problem has been fixed in version 3.0.6.RELEASE-10.

We recommend that you upgrade your libspring-java packages.