========================================================================================== BlastChat Chat Client Component version 3.3 <= Cross Script Scripting (XSS) Vulnerability ========================================================================================== 1. OVERVIEW The BlastChat's chat client Component of Joomla 1.x, Joomla 1.5.x, Mambo 4.5, Mambo 4.6, Drupal 6 was vulnerable to Cross Script Scripting (XSS) Vulnerability. 2. PRODUCT DESCRIPTION The BlastChat Chat Client Component is a widely-used Blastchat chat client component designed for website communities from the smallest personal websites to the huge megasites who desire to provide their members and visitors with a superb chat experience. The client chat component is available in multiple CMSes including Joomla 1.x, Joomla 1.5.x, Mambo 4.5, Mambo 4.6, and Drupal 6. BlastChat has currently been serving chat to over 50.000+ websites. 3. VULNERABILITY DESCRIPTION The BlastChat's chat client Component does not properly escape "Itemid" parameter, which leads 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 Versions: 3.3 and lower 5. PROOF-OF-CONCEPT/EXPLOIT URL: /index.php?option=com_blastchatc&Itemid=-999 Affected Parameter: Itemid http://yehg.net/lab/pr0js/advisories/joomla/com_blastchatc_xss(Itemid).jpg 6. IMPACT As this is a multi-user chat application "component", the impact of XSS is huge, ranking from cookie theft to mass client exploits. 7. SOLUTION Upgrade to version 3.4 8. VENDOR Blastchat http://www.blastchat.com 9. CREDIT This vulnerability was discovered by Aung Khant, http://yehg.net, YGN Ethical Hacker Group, Myanmar. 10. DISCLOSURE TIME-LINE 08-11-2010: discovered vulnerability 08-11-2010: notified vendor 08-11-2010: vendor fixed vulnerability 08-14-2010: vendor released patched version - 3.4 08-26-2010: vulnerability disclosed 11. REFERENCES Original Advisory URL: http://yehg.net/lab/pr0js/advisories/joomla/[com_blastchatc]_cross_site_scripting What XSS Can Do: http://yehg.net/lab/pr0js/view.php/What%20XSS%20Can%20Do.pdf XSS FAQs: http://www.cgisecurity.com/articles/xss-faq.shtml XSS (wiki): http://en.wikipedia.org/wiki/Cross-site_scripting XSS (owasp): http://www.owasp.org/index.php/Cross-site_Scripting_(XSS) OWASP Top 10: http://www.owasp.org/index.php/Category:OWASP_Top_Ten_Project CWE-79: http://cwe.mitre.org/data/definitions/79.html #yehg [08-26-2010] --------------------------------- Best regards, YGN Ethical Hacker Group Yangon, Myanmar http://yehg.net Our Lab | http://yehg.net/lab Our Directory | http://yehg.net/hwd