[ GLSA 201612-10 ] libvirt

[GLSA]

Gentoo Linux Security Advisory

Title: libvirt: Directory traversal (GLSA 201612-10)
Severity: normal
Exploitable: local
Date: December 04, 2016
Bug(s): #568870
ID: 201612-10

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: app-emulation/libvirt
Vulnerable: < 1.2.21-r1
Unaffected: >= 1.2.21-r1
Architectures: All supported architectures


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: