1. OVERVIEW

The Joomla! web application was vulnerable to Cross Site Scripting
vulnerability.


2. PRODUCT DESCRIPTION

Joomla is a free and open source content management system (CMS) for
publishing content on the World Wide Web and intranets. It comprises a
model–view–controller (MVC) Web application framework that can also be
used independently.
Joomla is written in PHP, uses object-oriented programming (OOP)
techniques and software design patterns, stores data in a MySQL
database, and includes features such as page caching, RSS feeds,
printable versions of pages, news flashes, blogs, polls, search, and
support for language internationalization.


3. VULNERABILITY DESCRIPTION

Some URLs in Joomla! do not properly escape encoded user inputs that
lead to cross site scripting vulnerability.
For more information about this kind of vulnerability, see OWASP Top
10 - A2, WASC-8 and
CWE-79: Improper Neutralization of Input During Web Page Generation
('Cross-site Scripting').


4. VERSIONS AFFECTED

Joomla! 1.5.20  and lower


5. PROOF-OF-CONCEPT/EXPLOIT

http://yehg.net/lab/pr0js/training/view/misc/joomla-1.5.20_encoded-xss/


6. IMPACT

Attackers can compromise currently logged-in user/administrator
session and impersonate arbitrary user actions available under
/administrator/ functions.


7. SOLUTION

Upgrade to Joomla! 1.5.21


8. VENDOR

Joomla! Developer Team
http://www.joomla.org


9. CREDIT

This vulnerability was discovered by Aung Khant, http://yehg.net, YGN
Ethical Hacker Group, Myanmar.


10. DISCLOSURE TIME-LINE

2010-10-04: vulnerability discovered
2010-10-06: notified vendor
2010-10-09: vendor released fix
2010-10-09: vulnerability disclosed


11. REFERENCES

Vendor Advisory URL:
http://developer.joomla.org/security/news/9-security/10-core-security/322-20101001-core-xss-vulnerabilities.html
Original Advisory URL:
http://yehg.net/lab/pr0js/advisories/joomla/core/[joomla_1.5.20]_cross_site_scripting(XSS)
XSS FAQ: http://www.cgisecurity.com/xss-faq.html
OWASP Top 10: http://www.owasp.org/index.php/Category:OWASP_Top_Ten_Project
CWE-79: http://cwe.mitre.org/data/definitions/79.html




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Best regards,
YGN Ethical Hacker Group
Yangon, Myanmar
http://yehg.net
Our Lab | http://yehg.net/lab
Our Directory | http://yehg.net/hwd