Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2007.0730 -- [Appliance]
Google Search Application XSS Vulnerability
27 September 2007
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Google Search Appliance
Publisher: UK Centre for the Protection of National
Infrastructure (CPNI)
Operating System: Network Appliance
Impact: Cross-site Scripting
Access: Remote/Unauthenticated
Original Bulletin: http://www.cpni.gov.uk/Products/3402.aspx
- --------------------------BEGIN INCLUDED TEXT--------------------
________________________________________________________________________
CSIRTUK ADVISORY - 3402 dated 26.09.07 time 13:58
Centre for the Protection of National Infrastructure (CPNI)
________________________________________________________________________
Further details about CPNI, including information about our products
can be
found at www.cpni.gov.uk
Please note that CSIRTUK RSS Feeds are available from:
http://www.cpni.gov.uk/rss/advisories.xml
________________________________________________________________________
Title
=====
Google Search Application XSS Vulnerability
Detail
======
ID: 3402
Date: 26 September 2007 13:58
- ------------------------------------------------------------------------
- --------
Title: 3402 - Google Search Application XSS Vulnerability
Abstract: Description of a reported vulnerability in Google Search
Appliance by GovCERTUK.
Vendors affected:Google
Applications affected:Google Search Application
Advisory type: Information
Source: GovCERTUK
Reliability of source: Trusted
Source URL: http://www.govcertuk.gov.uk/
Issued: 26/09/07
Overview
On the 18th September 2007, a Ukrainian Website reported that a Cross
Site Scripting (XSS) vulnerability existed in the Google Search
Application. The Google Search Application can be used for searching a
local website, and is widely used on Internet facing websites to provide
search functionality both internally and externally.
http://www.xssed.com/news/40/Google_Search_Appliance_is_vulnerable_to_XSS/
Cross Site Scripting (XSS)
XSS is a common vulnerability that could allow malicious content to be
delivered by an attacker whilst spoofing a legitimate source. Examples
of an XSS vulnerability can be used for malicious activity include:
Attacking other users
An attacker could create a malicious web link that appears to be
legitimate, and distribute it to a large target audience (e.g. via email
or message board posts). The attacker would need to convince users to
visit the malicious site, and by using a .gov.uk URL it can add
significant credibility to this, as it appears to be hosted at a
legitimate, trusted domain. Anyone that follows the link would load a
webpage containing malicious code. This is then executed on the local
machine utilising vulnerabilities in the browser (see Appendix A)
allowing an attacker to take control of the local machine.
Phishing attacks
An attacker could send out a crafted email that, using social
engineering techniques convinces a user to visit a website. The link
that the user clicks however directs them to a site that the attacker
has crafted to look authentic. This site encourages the user to provide
personal information, which is then submitted to a site the attacker
controls.
Website defacement
Using XSS it could be possible for an attacker to alter the content of a
web page. This could include altering text as well as the addition of
damaging or defamatory statements. For example, an attacker could add a
political statement, or generally deface the site.
How this affects the Google Search Application
The Google Search Application is vulnerable to the above mentioned XSS
vulnerabilities. This means that a vulnerable website could be used to
deliver malicious content to an end user.
There are also more advanced attacks possible using XSS, including
persisting XSS code across sites, attacking intranet sites and proxy
browsing. However at this time it is not thought that the Google Search
Application is vulnerable to these advanced XSS attacks.
Mitigation Advice
GovCertUK advises that the Google Search Application be completely
disabled until Google issue a patch to resolve this vulnerability.
In addition to this there are steps that should be taken to prevent
further XSS exploitation:
All user input should be validated for potentially malicious input. For
example, an input field for a telephone number should be validated to
remove all non-numeric characters.
All user input should be encoded into HTML. This prevents special
characters, such as '&' or '<', from being interpreted as HTML itself.
Departments are reminded that proper content filtering will also help
prevent XSS and other vulnerabilities.
Appendix A
There are various browser vulnerabilities that exist that could allow an
attacker to gain control of the user's machine. Common vulnerabilities
include:
The RDS.Dataspace vulnerability (MS06-014)
http://www.microsoft.com/technet/security/Bulletin/MS06-014.mspx
The VML vulnerability (MS06-055)
http://www.microsoft.com/technet/security/Bulletin/MS06-055.mspx
The ANI vulnerability (MS07-017)
http://www.microsoft.com/technet/security/bulletin/MS07-017.mspx
________________________________________________________________________
CPNI values your feedback.
1. Which of the following most reflects the value of the advisory to
you?
(Place an 'X' next to your choice)
Very useful:__ Useful:__ Not useful:__
2. If you did not find it useful, why not?
3. Any other comments? How could we improve our advisories?
Thank you for your contribution.
________________________________________________________________________
CSIRTUK wishes to acknowledge the contributions of GovCERTUK for the
information contained in this advisory.
________________________________________________________________________
This advisory contains information released by the original author.
Some of the information may have changed since it was released. If the
issue affects you, it may be prudent to retrieve the advisory from the
site of the original source to ensure that you receive the most current
information concerning that problem.
Reference to any specific commercial product, process, or service by
trade name, trademark manufacturer, or otherwise, does not constitute or
imply its endorsement, recommendation, or favouring by CPNI. The views
and opinions of authors expressed within this notice shall not be used
for advertising or product endorsement purposes.
CPNI shall not accept responsibility for any errors or omissions
contained within this advisory. In particular, they shall not be liable
for any loss or damage whatsoever, arising from or in connection with
the usage of information contained within this advisory.
CSIRTUK is a member of the Forum of Incident Response and Security Teams
(FIRST) and has contacts with other international Incident Response Teams
(IRTs) in order to foster cooperation and coordination in incident
prevention, to prompt rapid reaction to incidents, and to promote
information sharing amongst its members and the community at large.
________________________________________________________________________
<End of CPNI Advisory>
- --------------------------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
iQCVAwUBRvsDuCh9+71yA2DNAQIDHwP/dSg+BYFK2HQuZRchcqrOT4vTOUMwueE1
sQ0SCEx3rKYI4OohlJUzrWuwfoojJ0jovNfPEr3+2iJQtXbganeC1IzUl+e/gawQ
U9txbrM9CGPR38lzIk82rirVng4eTFONLhqGkf+aWdvAdmgv4CDH6Vq38ZJqU9mN
t6yrMBPFaXA=
=HuIR
-----END PGP SIGNATURE-----