[ GLSA 200710-11 ] X Font Server: Multiple Vulnerabilities

[Pierre-Yves Rofes <py () gentoo org>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Gentoo Linux Security Advisory                           GLSA 200710-11
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
                                            http://security.gentoo.org/
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  Severity: High
     Title: X Font Server: Multiple Vulnerabilities
      Date: October 12, 2007
      Bugs: #185660, #194606
        ID: 200710-11

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Synopsis
========

Three vulnerabilities have been discovered in the X Font Server
possibly allowing local attackers to gain elevated privileges.

Background
==========

The X.Org X11 X Font Server provides a standard mechanism for an X
server to communicate with a font renderer.

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

    -------------------------------------------------------------------
     Package       /  Vulnerable  /                         Unaffected
    -------------------------------------------------------------------
  1  x11-apps/xfs       < 1.0.5                               >= 1.0.5

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

iDefense reported that the xfs init script does not correctly handle a
race condition when setting permissions of a temporary file
(CVE-2007-3103). Sean Larsson discovered an integer overflow
vulnerability in the build_range() function possibly leading to a
heap-based buffer overflow when handling "QueryXBitmaps" and
"QueryXExtents" protocol requests (CVE-2007-4568). Sean Larsson also
discovered an error in the swap_char2b() function possibly leading to a
heap corruption when handling the same protocol requests
(CVE-2007-4990).

Impact
======

The first issue would allow a local attacker to change permissions of
arbitrary files to be world-writable by performing a symlink attack.
The second and third issues would allow a local attacker to execute
arbitrary code with privileges of the user running the X Font Server,
usually xfs.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All X Font Server users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=x11-apps/xfs-1.0.5"

References
==========

  [ 1 ] CVE-2007-3103
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-3103
  [ 2 ] CVE-2007-4568
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-4568
  [ 3 ] CVE-2007-4990
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-4990

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

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

  http://security.gentoo.org/glsa/glsa-200710-11.xml

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
http://bugs.gentoo.org.

License
=======

Copyright 2007 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
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFHD+eHuhJ+ozIKI5gRAlcdAJ4t+dNJKPDJFQEte8XCtLiIcjzu1QCfdoaF
uFfqllq2K1mtyPSCW+jz6DU=
=iwzz
-----END PGP SIGNATURE-----