Mozilla Firefox before the Preview Release, Mozilla before 1.7.3, and Thunderbird before 0.8 allows untrusted Javascript code to read and write to the clipboard, and possibly obtain sensitive information, via script-generated events such as Ctrl-Ins.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9745
https://exchange.xforce.ibmcloud.com/vulnerabilities/17376
http://www.novell.com/linux/security/advisories/2004_36_mozilla.html
http://www.mozilla.org/projects/security/known-vulnerabilities.html#mozilla1.7.3
http://www.kb.cert.org/vuls/id/460528
http://security.gentoo.org/glsa/glsa-200409-26.xml
http://secunia.com/advisories/12526