Code injection

Mozilla Firefox before 2.0.0.8 and SeaMonkey before 1.1.5 do not properly implement JavaScript onUnload handlers, which allows remote attackers to run certain JavaScript code and access the location DOM hierarchy in the context of the next web site that is visited by a client...

CVE-2007-1094: Undefined Security Weakness

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...