Subject: [ASA-201611-2] libxml2: arbitrary code execution

Arch Linux Security Advisory ASA-201611-2
=========================================

Severity: Critical
Date    : 2016-11-01
CVE-ID  : CVE-2016-4658 CVE-2016-5131
Package : libxml2
Type    : arbitrary code execution
Remote  : Yes
Link    : https://security.archlinux.org/AVG-56

Summary
=======

The package libxml2 before version 2.9.4+12+ge905f08-1 is vulnerable to
arbitrary code execution.

Resolution
==========

Upgrade to 2.9.4+12+ge905f08-1.

# pacman -Syu "libxml2>=2.9.4+12+ge905f08-1"

The problems have been fixed upstream but no release is available yet.

Workaround
==========

None.

Description
===========

- CVE-2016-4658 (arbitrary code execution)

A use-after-free vulnerability via namespace nodes in XPointer ranges
was found in libxml2.

- CVE-2016-5131 (arbitrary code execution)

Bugs in xmlXPathEvalExpr and xmlXPtrRangeToFunction can lead to a use-
after-free and allow control of the instruction pointer.

Impact
======

A remote attacker is able to use a specially crafted XPath payload to
execute arbitrary code.

References
==========

https://git.gnome.org/browse/libxml2/commit/?id=c1d1f7121194036608bf555f08d3062a36fd344b
https://bugzilla.redhat.com/show_bug.cgi?id=1384424
https://git.gnome.org/browse/libxml2/commit/?id=9ab01a277d71f54d3143c2cf333c5c2e9aaedd9e
https://bugs.chromium.org/p/chromium/issues/detail?id=623378
https://security.archlinux.org/CVE-2016-4658
https://security.archlinux.org/CVE-2016-5131