raptor/raptor2 -- XXE in RDF/XML File Interpretation

Timothy D. Morgan reports:

In December 2011, VSR identified a vulnerability in multiple open
source office products (including OpenOffice, LibreOffice, KOffice,
and AbiWord) due to unsafe interpretation of XML files with custom
entity declarations. Deeper analysis revealed that the
vulnerability was caused by acceptance of external entities by the
libraptor library, which is used by librdf and is in turn used by
these office products.
In the context of office applications, these vulnerabilities could
allow for XML External Entity (XXE) attacks resulting in file theft
and a loss of user privacy when opening potentially malicious ODF
documents. For other applications which depend on librdf or
libraptor, potentially serious consequences could result from
accepting RDF/XML content from untrusted sources, though the impact
may vary widely depending on the context.