The Computer Emergency Response Team of Finland (CERT-FI) warns that a number of popular XML libraries may have security bugs. When unexpected values are found in XML elements, it may trigger loops, or memory out of bounds errors. Attackers may be able to use these to cause denial of service attacks at the very least, or launch hostile code at the worst. Some of these libraries include Python libexpat, Apache Xerces, and the Sun JDK and JRE 6 Update 14 or 19. Keep an eye here for update and patch information. (While they are Finnish, they have excellent English-language versions of their bulletins.)