libxml, libxml2 security update

CentOS Errata and Security Advisory CESA-2009:1206

libxml is a library for parsing and manipulating XML files. A Document Type
Definition (DTD) defines the legal syntax (and also which elements can be
used) for certain types of files, such as XML files.

A stack overflow flaw was found in the way libxml processes the root XML
document element definition in a DTD. A remote attacker could provide a
specially-crafted XML file, which once opened by a local, unsuspecting
user, would lead to denial of service (application crash). (CVE-2009-2414)

Multiple use-after-free flaws were found in the way libxml parses the
Notation and Enumeration attribute types. A remote attacker could provide
a specially-crafted XML file, which once opened by a local, unsuspecting
user, would lead to denial of service (application crash). (CVE-2009-2416)

Users should upgrade to these updated packages, which contain backported
patches to resolve these issues. For Red Hat Enterprise Linux 3, they
contain backported patches for the libxml and libxml2 packages. For Red Hat
Enterprise Linux 4 and 5, they contain backported patches for the libxml2
packages. The desktop must be restarted (log out, then log back in) for
this update to take effect.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2009-August/078230.html
https://lists.centos.org/pipermail/centos-announce/2009-August/078231.html
https://lists.centos.org/pipermail/centos-announce/2009-August/078236.html
https://lists.centos.org/pipermail/centos-announce/2009-August/078237.html

Affected packages:
libxml
libxml-devel
libxml2
libxml2-devel
libxml2-python

Upstream details at:
https://access.redhat.com/errata/RHSA-2009:1206