Multiple use-after-free vulnerabilities in libxml2 2.5.10, 2.6.16, 2.6.26, 2.6.27, and 2.6.32, and libxml 1.8.17, allow context-dependent attackers to cause a denial of service (application crash) via crafted (1) Notation or (2) Enumeration attribute types in an XML file, as demonstrated by the Codenomicon XML fuzzing framework.

A stack overflow flaw was found in libxml by parsing root XML document element DTD definition. Providing a specially-crafted XML file would lead to excessive stack growth and denial of service (application crash), when opened by a victim.