Mozilla Firefox before 3.0.9, Thunderbird, and SeaMonkey do not properly implement the Same Origin Policy for (1) XMLHttpRequest, involving a mismatch for a document's principal, and (2) XPCNativeWrapper.toString, involving an incorrect __proto__ scope, which allows remote attackers to conduct cross-site scripting (XSS) attacks and possibly other attacks via a crafted document.
The nsXMLDocument::OnChannelRedirect function in Mozilla Firefox before 2.0.0.17, Thunderbird before 2.0.0.17, and SeaMonkey before 1.1.12 allows remote attackers to bypass the Same Origin Policy and execute arbitrary JavaScript code via unknown vectors.
Mozilla Firefox before 2.0.0.17 and 3.x before 3.0.2, Thunderbird before 2.0.0.17, and SeaMonkey before 1.1.12 allow remote attackers to create documents that lack script-handling objects, and execute arbitrary code with chrome privileges, via vectors related to (1) the document.loadBindingDocument function and (2) XSLT.