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Gentoo Linux Security Advisory                           GLSA 201612-10
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                                           https://security.gentoo.org/
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 Severity: Normal
    Title: libvirt: Directory traversal
     Date: December 04, 2016
     Bugs: #568870
       ID: 201612-10

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Synopsis
========

Libvirt is vulnerable to directory traversal when using Access Control
Lists (ACL).

Background
==========

libvirt is a C toolkit for manipulating virtual machines.

Affected packages
=================

    -------------------------------------------------------------------
     Package              /     Vulnerable     /            Unaffected
    -------------------------------------------------------------------
  1  app-emulation/libvirt      < 1.2.21-r1              >= 1.2.21-r1

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

Normally, only privileged users can coerce libvirt into creating or
opening existing files using the virStorageVol APIs; and such users
already have full privilege to create any domain XML.

But in the case of fine-grained ACLs, it is feasible that a user can be
granted storage_vol:create but not domain:write, and it violates
assumptions if such a user can abuse libvirt to access files outside of
the storage pool.

Impact
======

When fine-grained Access Control Lists (ACL) are in effect, an
authenticated local user with storage_vol:create permission but without
domain:write permission maybe able to create or access arbitrary files
outside of the storage pool.

Workaround
==========

Don't make use of fine-grained Access Control Lists (ACL) in libvirt;
In Gentoo, libvirt's ACL support is disable by default unless you
enable the "policykit" USE flag.

Resolution
==========

All libvirt users should upgrade to the latest version:

  # emerge --sync
  # emerge --ask --oneshot -v ">=app-emulation/libvirt-1.2.21-r1"

References
==========

[ 1 ] CVE-2015-5313
      http://nvd.nist.gov/nvd.cfm?cvename=CVE-2015-5313

Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

 https://security.gentoo.org/glsa/201612-10

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
https://bugs.gentoo.org.

License
=======

Copyright 2016 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

http://creativecommons.org/licenses/by-sa/2.5