Topic

Updated mingw32-libxml2 packages that fix several security issues are now
available for Red Hat Enterprise Linux 6. This advisory also contains
information about future updates for the mingw32 packages, as well as the
deprecation of the packages with the release of Red Hat
Enterprise Linux 6.4.

The Red Hat Security Response Team has rated this update as having
important 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.

Description

These packages provide the libxml2 library, a development toolbox providing
the implementation of various XML standards, for users of MinGW (Minimalist
GNU for Windows).

IMPORTANT NOTE: The mingw32 packages in Red Hat Enterprise Linux 6 will no
longer be updated proactively and will be deprecated with the release of
Red Hat Enterprise Linux 6.4. These packages were provided to support other
capabilities in Red Hat Enterprise Linux and were not intended for direct
customer use. Customers are advised to not use these packages with
immediate effect. Future updates to these packages will be at Red Hat's
discretion and these packages may be removed in a future minor release.

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-2011-3919)

A heap-based buffer underflow flaw was found in the way libxml2 decoded
certain entities. 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-2012-5134)

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. (CVE-2012-0841)

Multiple flaws were found in the way libxml2 parsed certain XPath (XML Path
Language) 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. (CVE-2010-4008, CVE-2010-4494,
CVE-2011-2821, CVE-2011-2834)

Two heap-based buffer overflow flaws were found in the way libxml2 decoded
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-2011-0216,
CVE-2011-3102)

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-2011-1944)

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.
(CVE-2011-3905)

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.

All users of mingw32-libxml2 are advised to upgrade to these updated
packages, which contain backported patches to correct these issues.

Solution

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

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64

Fixes

• BZ - 645341 - CVE-2010-4008 libxml2: Crash (stack frame overflow or NULL pointer dereference) by traversal of XPath axis
• BZ - 665963 - CVE-2010-4494 libxml2: double-free in XPath processing code
• BZ - 709747 - CVE-2011-1944 libxml, libxml2: Heap-based buffer overflow by adding new namespace node to an existing nodeset or merging nodesets
• BZ - 724906 - CVE-2011-0216 libxml2: Off-by-one error leading to heap-based buffer overflow in encoding
• BZ - 735712 - CVE-2011-2821 libxml2: double free caused by malformed XPath expression in XSLT
• BZ - 735751 - CVE-2011-2834 libxml2: double-free caused by malformed XPath expression in XSLT
• BZ - 767387 - CVE-2011-3905 libxml2 out of bounds read
• BZ - 771896 - CVE-2011-3919 libxml2: Heap-based buffer overflow when decoding an entity reference with a long name
• BZ - 787067 - CVE-2012-0841 libxml2: hash table collisions CPU usage DoS
• BZ - 822109 - CVE-2011-3102 libxml: An off-by-one out-of-bounds write by XPointer part evaluation
• BZ - 880466 - CVE-2012-5134 libxml2: Heap-buffer-underflow in xmlParseAttValueComplex

CVEs

• CVE-2011-0216
• CVE-2010-4008
• CVE-2011-1944
• CVE-2011-2834
• CVE-2011-2821
• CVE-2010-4494
• CVE-2011-3919
• CVE-2011-3905
• CVE-2012-0841
• CVE-2011-3102
• CVE-2012-5134

References

• https://access.redhat.com/security/updates/classification/#important