Hi, This is a cross-zone scripting vulnerability. FeedReader uses the IE browser control to render HTML. The RSS reader converts the RSS item data to a formatted HTML file and caches it locally. When the user clicks on the RSS item, the RSS reader displays the local cached file, and any script in that file (or external references) will run in Local Zone. Therefore, an attacker can create/manipulate an RSS feed that will execute arbitrary code on the user's machine. Btw, according to Bugtrag (http://www.securityfocus.com/bid/25849/exploit) an attacker must convince the victim into subscribing a malicious RSS feed. As I've already discussed this in my blog post (http://aviv.raffon.net/2007/08/16/VistaGadgetsGoneWild.aspx) regarding the Windows Vista's RSS gadget, this claim is not true. In today's Web2.0 era, if a remote code execution vulnerability exists in RSS readers, it is very easy to create an RSS based worm. --Aviv. -----Original Message----- From: Guy Mizrahi [mailto:guy@xxxxxxxxxxxxxx] Sent: Friday, September 28, 2007 3:02 PM To: bugtraq@xxxxxxxxxxxxxxxxx Subject: feedreader3 has XSS vulnerability Hello, I have found that feedreader3 has XSS vulnerability in its internal browser. When I post a script into wordpress( like <script>alert("XSS")</script>, the RSS feed in the internal browser is vulnerable and show an alert box. POC movie here: http://www.hacking.org.il/demos/feedreader3.wmv Guy Mizrahi (ZuLL) Hebrew blog: http://www.hacking.org.il
