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.
Exploitability
AV:NAC:LAu:NImpact
C:NI:PA:N5/AV:N/AC:L/Au:N/C:N/I:P/A:N