Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2008.0310 -- [Win][UNIX/Linux]
Adobe Flash Player may load arbitrary, malformed cross-domain policy files
26 March 2008
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Adobe Flash Player
Publisher: US-CERT
Operating System: Windows
UNIX variants (UNIX, Linux, OSX)
Impact: Cross-site Scripting
Modify Arbitrary Files
Create Arbitrary Files
Inappropriate Access
Access: Remote/Unauthenticated
Original Bulletin: http://www.kb.cert.org/vuls/id/935737
- --------------------------BEGIN INCLUDED TEXT--------------------
Vulnerability Note VU#935737
Adobe Flash Player may load arbitrary, malformed cross-domain policy files
Overview
Adobe Flash Player may load arbitrary, malformed cross-domain policy
files. This could allow an attacker to control cross-domain data loading,
potentially allowing the attacker to gain access to sensitive information
or to manipulate content in other domains.
I. Description
Adobe Flash Player is a widely deployed application for multimedia
viewing on the internet. A vulnerability exists in the way that Flash
Player handles cross-domain policy files. An attacker could use a
specially crafted cross-domain policy file to circumvent a site's Flash
content data loading security polices.
- From Security changes in Flash Player 9:
There is a possibility that a file on a server that does not appear to
be a policy file may in fact be used as a policy file. For example, if
a server permits uploads by users, but does not intend to open data for
cross-domain access, it is possible that a user could deliberately
construct a policy file but disguise it as a different type of file,
such as an ordinary text, XML, or HTML file, or even as a binary type,
such as a PNG or JPEG image file. A user who successfully uploaded this
disguised policy file could then write a SWF file that takes advantage
of the disguised policy file to load data from outside the server's
domain.
II. Impact
A remote, unauthenticated attacker may be able to conduct cross-domain
and cross-site scripting attacks on sites hosting Flash content. This
could allow the attacker to read data or modify Flash content, possibly
gaining access to sensitive information or spoofing web site content.
III. Solution
Adobe has released an update for Flash Player to address this
vulnerability. Please see Adobe Security bulletin APSB07-20.
Limit access to Flash files
Limiting access to untrusted Flash files can prevent cross-site
scripting attacks that use Flash files. Disable ActiveX controls in the
Internet Zone in Microsoft Internet Explorer. See Securing Your Web
Browser for more information. Consider using the NoScript extension to
whitelist web sites that can run Flash in Mozilla browsers such as
Firefox. See the NoScript FAQ for more information.
Systems Affected
Vendor Status Date Updated
Adobe Vulnerable 24-Mar-2008
References
http://www.adobe.com/support/security/bulletins/apsb07-20.html
http://www.adobe.com/devnet/flash/articles/fplayer_security.html
http://www.adobe.com/devnet/flashplayer/articles/fplayer9_security.html
http://www.adobe.com/devnet/flashplayer/articles/cross_domain_policy.html
http://jvn.jp/jp/JVN%2345675516/index.html
http://secunia.com/advisories/28161/
Credit
Adobe credits Toshiharu Sugiyama of UBsecure, Inc. and JPCERT/CC for
reporting this vulnerability.
This document was written by Dean Reges and Art Manion.
Other Information
Date Public 12/19/2007
Date First Published 03/25/2008 08:14:06 AM
Date Last Updated 03/25/2008
CERT Advisory
CVE Name CVE-2007-6243
US-CERT Technical Alerts TA07-355A
Metric 23.29
Document Revision 101
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
http://www.auscert.org.au/render.html?cid=1980
If you believe that your computer system has been compromised or attacked in
any way, we encourage you to let us know by completing the secure National IT
Incident Reporting Form at:
http://www.auscert.org.au/render.html?it=3192
===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072
Internet Email: auscert@auscert.org.au
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
iQCVAwUBR+mjcSh9+71yA2DNAQL2FgP+NGlKMFr2tEiB28g+4bgASgPdwqDa09WI
EfrSTbGOqTPuTdfhPHQl1xaTORu2epPJ9E+CB9wHe7480jrCYJguE7YS5pk+1lFy
Nv2AxkrML95AX23r+KHmlYrSmPXVt6/EmaKQxxiBgvhfiOUVjvimPQS4ikCtaXOc
91J7OYR1pyg=
=JrBy
-----END PGP SIGNATURE-----