Vous êtes ici: index » cert » avis

Avis du CERT RENATER

Par défaut, cette page vous affichera les derniers messages envoyés par le CERT RENATER à la communauté. Vous pouvez affiner par année ou par type de message. Si aucun critère n'est précisé, seuls les derniers messages sont affichés

Date : Tue, 17 Jun 2008 17:31:03 +0200
Type : VULN
Sujet : CERT-Renater : 2008/VULN222 (iDefense: Multiple Vendor FreeType2 Multiple Vulnerabilities)
====================================================================                                    CERT-Renater

                         Note d'Information No. 2008/VULN222
_____________________________________________________________________

DATE                      : 17/06/2008

HARDWARE PLATFORM(S)      : /

OPERATING SYSTEM(S)       : Systems running Freetype.

======================================================================
http://labs.idefense.com/intelligence/vulnerabilities/display.php?idq7
http://labs.idefense.com/intelligence/vulnerabilities/display.php?idq5
http://labs.idefense.com/intelligence/vulnerabilities/display.php?idq6
______________________________________________________________________


iDefense Security Advisory 06.10.08
http://labs.idefense.com/intelligence/vulnerabilities/
Jun 10, 2008

I. BACKGROUND

FreeType2 is an open source library for parsing fonts that is used by
many applications. This includes projects such as X.Org, Second Life,
and the Sun Java JRE. For more information, please see the vendor's
website at the following URL.

http://freetype.sourceforge.net/freetype2/

II. DESCRIPTION

Remote exploitation of multiple heap overflow vulnerabilities in the
FreeType2 library, as included in various vendors' operating systems,
could allow an attacker to execute arbitrary code with the privileges
of the affected application.

Two vulnerabilities exist within the code responsible for parsing font
files.

The first vulnerability occurs when parsing Printer Font Binary (PFB)
format font files. PFB files contain various data structures, some of
which are stored in a tabular format. When parsing tables, the code
doesn't correctly validate a value used as an array index into a heap
buffer. The calculation contains an off-by-one error, which can result
in a heap overflow.

The second vulnerability occurs when parsing TrueType Font (TTF) font
files. TrueType font files contain "font programs" that are executed in
a TrueType virtual machine. One of the instructions in the instruction
set is 'SHC', which is used to shift a contour in the font by a
specified value. When parsing this instruction, the code doesn't
correctly validate an array index, which leads to an off-by-one heap
overflow.

III. ANALYSIS

Exploitation of these vulnerabilities results in the execution of
arbitrary code with the privileges of the application using the
library. Since FreeType2 is a library and not a standalone application,
the exploitation vector will vary. iDefense Labs verified that local
privilege escalation was possible via the X.Org Xserver.

IV. DETECTION

iDefense has confirmed the existence of these vulnerabilities in
FreeType2 version 2.3.5. Previous versions may also be affected.

V. WORKAROUND

iDefense is currently unaware of any workarounds for these issues.
Changing the permissions on the freetype.so library may not always be
effective since applications that run with root privileges are not
restricted by file permissions.

VI. VENDOR RESPONSE

The FreeType maintainers addressed these vulnerabilities with the
release of version 2.3.6. For more information, refer to the release
notes at the following URL.

http://sourceforge.net/project/shownotes.php?group_id157&release_id`5780

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2008-1808 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org/), which standardizes names for
security problems.

VIII. DISCLOSURE TIMELINE

06/03/2008  Initial vendor notification
06/04/2008  Initial vendor response
06/10/2008  Coordinated public disclosure

IX. CREDIT

These vulnerabilities were reported to iDefense by regenrecht.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php

Free tools, research and upcoming events
http://labs.idefense.com/

X. LEGAL NOTICES

Copyright © 2008 iDefense, Inc.

Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
written consent of iDefense. If you wish to reprint the whole or any
part of this alert in any other medium other than electronically,
please e-mail customerservice@idefense.com for permission.

Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
  There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct,
indirect, or consequential loss or damage arising from use of, or
reliance on, this information.
_______________________________________________


iDefense Security Advisory 06.10.08
http://labs.idefense.com/intelligence/vulnerabilities/
Jun 10, 2008

I. BACKGROUND

FreeType2 is an open source library for parsing fonts that is used by
many applications. This includes projects such as X.Org, Second Life,
and the Sun Java JRE. For more information, please see the vendor's
website at the following URL.

http://freetype.sourceforge.net/freetype2/

II. DESCRIPTION

Remote exploitation of an integer overflow vulnerability in the
FreeType2 library, as included in various vendors' operating systems,
could allow an attacker to execute arbitrary code with the privileges
of the affected application.

The vulnerability exists within the code responsible for parsing Printer
Font Binary (PFB) format font files. PFB files contain a section known
as the "Private" dictionary table which is used to describe how
characters are constructed. When parsing this data structure, a series
of 16-bit length values are read in from the file. These values are
added together and used to allocate a dynamic buffer. The addition can
result in an integer overflow, which subsequently leads to a heap
overflow.

III. ANALYSIS

Exploitation of this vulnerability results in the execution of arbitrary
code with the privileges of the application using the library. Since
FreeType2 is a library and not a standalone application, the
exploitation vector will vary. iDefense Labs verified that local
privilege escalation was possible via the X.Org Xserver.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability in FreeType2
version 2.3.5. Previous versions may also be affected.

V. WORKAROUND

iDefense is currently unaware of any workarounds for this issue.
Changing the permissions on the freetype.so library may not always be
effective since applications that run with root privileges are not
restricted by file permissions.

VI. VENDOR RESPONSE

The FreeType maintainers addressed this vulnerability with the release
of version 2.3.6. For more information, refer to the release notes at
the following URL.

http://sourceforge.net/project/shownotes.php?group_id157&release_id`5780

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2008-1806 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org/), which standardizes names for
security problems.

VIII. DISCLOSURE TIMELINE

06/03/2008  Initial vendor notification
06/04/2008  Initial vendor response
06/10/2008  Coordinated public disclosure

IX. CREDIT

This vulnerability was reported to iDefense by regenrecht.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php

Free tools, research and upcoming events
http://labs.idefense.com/

X. LEGAL NOTICES

Copyright © 2008 iDefense, Inc.

Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
written consent of iDefense. If you wish to reprint the whole or any
part of this alert in any other medium other than electronically,
please e-mail customerservice@idefense.com for permission.

Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
  There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct,
indirect, or consequential loss or damage arising from use of, or
reliance on, this information.
_______________________________________________


iDefense Security Advisory 06.10.08
http://labs.idefense.com/intelligence/vulnerabilities/
Jun 10, 2008

I. BACKGROUND

FreeType2 is an open source library for parsing fonts that is used by
many applications. This includes projects such as X.Org, Second Life,
and the Sun Java JRE. For more information, please see the vendor's
website at the following URL.

http://freetype.sourceforge.net/freetype2/

II. DESCRIPTION

Remote exploitation of a memory corruption vulnerability in the
FreeType2 library, as included in various vendors' operating systems,
could allow an attacker to execute arbitrary code with the privileges
of the affected application.

The vulnerability exists within the code responsible for parsing Printer
Font Binary (PFB) format font files. By providing an invalid 'number of
axes' in the file, it is possible to cause the code to call the free()
function on areas of memory that were not dynamically allocated. This
can lead to memory corruption, which can allow for the execution of
arbitrary code.

III. ANALYSIS

Exploitation of this vulnerability results in the execution of arbitrary
code with the privileges of the application using the library. Since
FreeType2 is a library and not a standalone application, the
exploitation vector will vary. iDefense Labs verified that local
privilege escalation was possible via the X.Org Xserver.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability in FreeType2
version 2.3.5. Previous versions may also be affected.

V. WORKAROUND

iDefense is currently unaware of any workarounds for this issue.
Changing the permissions on the freetype.so library may not always be
effective since applications that run with root privileges are not
restricted by file permissions.

VI. VENDOR RESPONSE

The FreeType maintainers addressed this vulnerability with the release
of version 2.3.6. For more information, refer to the release notes at
the following URL.

http://sourceforge.net/project/shownotes.php?group_id157&release_id`5780

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2008-1807 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org/), which standardizes names for
security problems.

VIII. DISCLOSURE TIMELINE

06/03/2008  Initial vendor notification
06/04/2008  Initial vendor response
06/10/2008  Coordinated public disclosure

IX. CREDIT

This vulnerability was reported to iDefense by regenrecht.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php

Free tools, research and upcoming events
http://labs.idefense.com/

X. LEGAL NOTICES

Copyright © 2008 iDefense, Inc.

Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
written consent of iDefense. If you wish to reprint the whole or any
part of this alert in any other medium other than electronically,
please e-mail customerservice@idefense.com for permission.

Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
  There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct,
indirect, or consequential loss or damage arising from use of, or
reliance on, this information.
_______________________________________________


======================================================================

           =========================================================
           Les serveurs de référence du CERT-Renater
           http://www.urec.fr/securite
           http://www.cru.fr/securite
           http://www.renater.fr
           =========================================================
           + CERT-RENATER          | tel : 01-53-94-20-44          +
           + 151 bd de l'Hopital   | fax : 01-53-94-20-41          +
           + 75013 Paris           | email: certsvp@renater.fr     +
           =========================================================