The XULDocument.persist function in Mozilla, Firefox before 1.5.0.1, and SeaMonkey before 1.0 does not validate the attribute name, which allows remote attackers to execute arbitrary Javascript by injecting RDF data into the user's localstore.rdf file.

Mozilla Firefox before 1.5.0.1, Thunderbird 1.5 if running Javascript in mail, and SeaMonkey before 1.0 allow remote attackers to execute arbitrary code by changing an element's style from position:relative to position:static, which causes Gecko to operate on freed memory.