The libxml2 library is a development toolbox providing the implementation of various XML standards.
A heap-based buffer overflow flaw was found in the way libxml2 decoded entity references with long names. A remote attacker could provide a specially-crafted XML file that, when opened in an application linked against libxml2, would cause the application to crash or, potentially, execute arbitrary code with the privileges of the user running the application. (CVE-2011-3919)
All users of libxml2 are advised to upgrade to these updated packages, which contain a backported patch to correct this issue. The desktop must be restarted (log out, then log back in) for this update to take effect.