CVE-2003-1328
The showHelp() function in Microsoft Internet Explorer 5.01, 5.5, and 6.0 supports certain types of pluggable protocols that allow remote attackers to bypass the cross-domain security model and execute arbitrary code, aka "Improper Cross Domain Security Validation with ShowHelp functionality."
Date published : 2004-09-01
http://www.securityfocus.com/bid/6780
http://archives.neohapsis.com/archives/bugtraq/2003-02/0083.html