It was discovered that libxslt, an XSLT processing runtime library,
could be coerced into executing arbitrary code via a buffer overflow
when an XSL style sheet file with a long XSLT “transformation match”
condition triggered a large number of steps.
Read the full story: DSA-1589 libxslt – buffer overflow: http://www.debian.org/security/2008/dsa-1589