The line-breaking implementation in Mozilla Firefox before 3.5.16 and 3.6.x before 3.6.13, Thunderbird before 3.0.11 and 3.1.x before 3.1.7, and SeaMonkey before 2.0.11 on Windows does not properly handle long strings, which allows remote attackers to execute arbitrary code via a crafted document.write call that triggers a buffer over-read.
http://lists.fedoraproject.org/pipermail/package-announce/2010-December/052502.html
http://lists.fedoraproject.org/pipermail/package-announce/2010-December/052504.html
http://lists.opensuse.org/opensuse-security-announce/2011-01/msg00002.html
http://secunia.com/advisories/42716
http://secunia.com/advisories/42818
http://www.debian.org/security/2010/dsa-2132
http://www.mandriva.com/security/advisories?name=MDVSA-2010:251
http://www.mandriva.com/security/advisories?name=MDVSA-2010:258
http://www.mozilla.org/security/announce/2010/mfsa2010-75.html
http://www.securityfocus.com/bid/45345
http://www.securitytracker.com/id?1024846
http://www.securitytracker.com/id?1024848
http://www.vupen.com/english/advisories/2011/0030
https://bugzilla.mozilla.org/show_bug.cgi?id=608336
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12342