Internet Explorer 5.01 through 6 allows remote attackers to spoof arbitrary web sites by injecting content from one window into another window whose name is known but resides in a different domain, as demonstrated using a pop-up window on a trusted web site, aka the "window injection" vulnerability. NOTE: later research shows that Internet Explorer 7 on Windows XP SP2 is also vulnerable.
Internet Explorer 5.01 SP4 up to 6 on various Windows operating systems, including IE 6.0.2900.2180 on Windows XP, allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via a web page with embedded CLSIDs that reference certain COM objects that are not ActiveX controls, as demonstrated using the JVIEW Profiler (Javaprxy.dll). NOTE: the researcher says that the vendor could not reproduce this problem.
Microsoft Internet Explorer 5.01 through 6 allows remote attackers to execute arbitrary code via HTML elements with a certain crafted tag, which leads to memory corruption.