Moderate: expat security update
Security Advisory: Moderate
Updated expat packages that fix two security issues are now available for
Red Hat Enterprise Linux 5 and 6.
The Red Hat Security Response Team has rated this update as having moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.
Expat is a C library written by James Clark for parsing XML documents.
A denial of service flaw was found in the implementation of hash arrays in
Expat. An attacker could use this flaw to make an application using Expat
consume an excessive amount of CPU time by providing a specially-crafted
XML file that triggers multiple hash function collisions. To mitigate
this issue, randomization has been added to the hash function to reduce the
chance of an attacker successfully causing intentional collisions.
(CVE-2012-0876)
A memory leak flaw was found in Expat. If an XML file processed by an
application linked against Expat triggered a memory re-allocation failure,
Expat failed to free the previously allocated memory. This could cause the
application to exit unexpectedly or crash when all available memory is
exhausted. (CVE-2012-1148)
All Expat users should upgrade to these updated packages, which contain
backported patches to correct these issues. After installing the updated
packages, applications using the Expat library must be restarted for the
update to take effect.
Before applying this update, make sure all previously-released errata
relevant to your system have been applied.
This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/knowledge/articles/11258
Vulmon