Hello Full-Disclosure! I want to warn you about security vulnerability in widget Cumulus for BlogEngine.NET. ----------------------------- Advisory: Vulnerability in widget Cumulus for BlogEngine.NET ----------------------------- URL: http://websecurity.com.ua/4184/ ----------------------------- Affected product: all versions of Cumulus for BlogEngine.NET. ----------------------------- Timeline: 30.04.2010 - found vulnerability. 10.05.2010 - disclosed at my site. 11.05.2010 - informed developers. ----------------------------- Details: This is Cross-Site Scripting vulnerability. This XSS is similar to XSS vulnerability in WP-Cumulus and other web applications which I already reported to security mailing lists, because it's using tagcloud.swf made by author of WP-Cumulus. About millions of flash files tagcloud.swf which are vulnerable to XSS attacks I mentioned in my article XSS vulnerabilities in 34 millions flash files (http://www.webappsec.org/lists/websecurity/archive/2010-01/msg00035.html). XSS: http://site/Blog/widgets/Cumulus/tagcloud.swf?mode=tags&tagcloud=%3Ctags%3E%3Ca+href='javascript:alert(document.cookie)'+style='font-size:+40pt'%3EClick%20me%3C/a%3E%3C/tags%3E Code will execute after click. It's strictly social XSS. Also it's possible to conduct (like in WP-Cumulus) HTML Injection attack, including in those flash files which have protection (in flash files or via WAF) against javascript and vbscript URI in parameter tagcloud. HTML Injection: http://site/Blog/widgets/Cumulus/tagcloud.swf?mode=tags&tagcloud=%3Ctags%3E%3Ca+href='http://websecurity.com.ua'+style='font-size:+40pt'%3EClick%20me%3C/a%3E%3C/tags%3E Best wishes & regards, MustLive Administrator of Websecurity web site http://websecurity.com.ua _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/