STG Security Advisory: [SSA-20030701-02] Verity K2 Toolkit Query Builder XSS
Vulnerability

Revision 1.0
Date Published: 2003-07-01 (KST)
Last Update: 2003-07-01
Disclosed by SSR Team (advisory@stgsecurity.com)


Summary
===================
Verity's K2 Toolkit provides e-commerce developers with text retrieval
capabilities and application integration features necessary for
customization including catalog navigation and content search functions.

Verity's K2 Toolkit has a XSS vulnerability in Query Builder.

Vulnerability Class
===================
Implementation Error: Inappropriate Input Validation

Details
=======
Query Builder in Verity K2 Toolkit executes a malicious JavaScript command
injected in query string when displaying error messages.

Proof of Concept:
http://[victim site]/[search].jsp?[query]=><img src=javascript:alert(document.cookie)>

Result:
Internal Servlet Error: Error E1-0111 (Query Builder): Syntax error in query
string near character [foo]
Error E1-0111 (Query Builder): Syntax error in query string near character
[bar]
Error E1-0114 (Query Builder): Error parsing query: [JAVASCRIPT RUNS HERE!]
...

Using this cross site scripting vulnerability, an attacker can hijack the
session of an administrator and deploy viruses or worms via vulnerable  web
browsers.

Impact
======
At August 2002, Eye on Security released an article entitled "Bypassing
JavaScript Filters - the Flash! Attack" on the  attacking method utilizing
cross site scripting vulnerabilities. A highly effective automated tool
using this method for session hijacking in the wild enables a hacker to
acquire the privilege of administrators and to alter or erase the web pages
of an victim site.

Workaround
==========
To workaround this problem, programmers must implement below exception
process mechanisms.

1. Catch exceptions and redirect users to a static error page predefined.
2. Log all errors to a log file for your debugging purpose.


Affected Products
==================
Verity K2 Toolkit v2.20 for RS/6000 is vulnerable.
We don't know whether another product has this vulnerability.


Vendor Status: UNKNOWN
===================
2003-06-17 Verity notified.
2003-06-18 Verity replied.
2003-06-18 Second attempt at vendor contact.
2003-06-23 Third attempt at vendor contact.
2003-06-24 Verity resisted to follow up the problem.
2003-07-01 Public disclosure

Credits
=======
Jeremy Bae at STG Security SSR Team

About STG Security
==================
STG Security Inc. is a affiliated company of STG Group which has its head
office in the States founded in march 2000. Its core business area is
professional penetration testing, security code review and BS7799 consulting
services.

http://www.stgsecurity.com/

Phone +82-2-6333-4500
FAX +82-2-6333-4545