CVE-2007-1094

Microsoft Internet Explorer 7 allows remote attackers to cause a denial of service NULL dereference and application crash via JavaScript onUnload handlers that modify the structure of a document...

security flaw

Mozilla Firefox 1.5.0.9 and 2.0.0.1, and SeaMonkey before 1.0.8 allow remote attackers to execute arbitrary code via JavaScript onUnload handlers that modify the structure of a document, wich triggers memory corruption due to the lack of a finalize hook on DOM window objects...