4.155. libxml2

Updated libxml2 packages that fix several security issues and various bugs are now available for Red Hat Enterprise Linux 6.
The Red Hat Security Response Team has rated this update as having low security impact. Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) associated with each description below.
The libxml2 library is a development toolbox providing the implementation of various XML standards. One of those standards is the XML Path Language (XPath), which is a language for addressing parts of an XML document.

Security Fixes

CVE-2011-0216
An off-by-one error, leading to a heap-based buffer overflow, was found in the way libxml2 parsed certain XML files. A remote attacker could provide a specially-crafted XML file that, when opened in an application linked against libxml2, would cause the application to crash or, potentially, execute arbitrary code with the privileges of the user running the application.
CVE-2011-1944
An integer overflow flaw, leading to a heap-based buffer overflow, was found in the way libxml2 parsed certain XPath expressions. If an attacker were able to supply a specially-crafted XML file to an application using libxml2, as well as an XPath expression for that application to run against the crafted file, it could cause the application to crash or, possibly, execute arbitrary code.
CVE-2010-4008, CVE-2010-4494, CVE-2011-2821, CVE-2011-2834
Multiple flaws were found in the way libxml2 parsed certain XPath expressions. If an attacker were able to supply a specially-crafted XML file to an application using libxml2, as well as an XPath expression for that application to run against the crafted file, it could cause the application to crash.
Note: Red Hat does not ship any applications that use libxml2 in a way that would allow the CVE-2011-1944, CVE-2010-4008, CVE-2010-4494, CVE-2011-2821, and CVE-2011-2834 flaws to be exploited; however, third-party applications may allow XPath expressions to be passed which could trigger these flaws.
Red Hat would like to thank the Google Security Team for reporting the CVE-2010-4008 issue. Upstream acknowledges Bui Quang Minh from Bkis as the original reporter of CVE-2010-4008.

Bug Fixes

BZ#732335
A number of patches have been applied to harden the XPath processing code in libxml2, such as fixing memory leaks, rounding errors, XPath numbers evaluations, and a potential error in encoding conversion.
All users of libxml2 are advised to upgrade to these updated packages, which contain backported patches to correct these issues. The desktop must be restarted (log out, then log back in) for this update to take effect.
Updated libxml2 packages that fix two security issues are now available for Red Hat Enterprise Linux 6.
The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) associated with each description below.
The libxml2 library is a development toolbox providing the implementation of various XML standards.

Security Fixes

CVE-2011-3919
A heap-based buffer overflow flaw was found in the way libxml2 decoded entity references with long names. A remote attacker could provide a specially-crafted XML file that, when opened in an application linked against libxml2, would cause the application to crash or, potentially, execute arbitrary code with the privileges of the user running the application.
CVE-2011-3905
An out-of-bounds memory read flaw was found in libxml2. A remote attacker could provide a specially-crafted XML file that, when opened in an application linked against libxml2, would cause the application to crash.
All users of libxml2 are advised to upgrade to these updated packages, which contain backported patches to correct these issues. The desktop must be restarted (log out, then log back in) for this update to take effect.
Updated libxml2 packages that fix one security issue 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. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) associated with each description below.
The libxml2 library is a development toolbox providing the implementation of various XML standards.

Security Fix

CVE-2012-0841
It was found that the hashing routine used by libxml2 arrays was susceptible to predictable hash collisions. Sending a specially-crafted message to an XML service could result in longer processing time, which could lead to a denial of service. To mitigate this issue, randomization has been added to the hashing function to reduce the chance of an attacker successfully causing intentional collisions.
All users of libxml2 are advised to upgrade to these updated packages, which contain a backported patch to correct this issue. The desktop must be restarted (log out, then log back in) for this update to take effect.