Mozilla Firefox 0.9.2 allows web sites to set cookies for country-specific top-level domains, such as .ltd.uk, .plc.uk, and .sch.uk, which could allow remote attackers to perform a session fixation attack and hijack a user's HTTP session. NOTE: it was later reported that 2.x is also affected.
https://exchange.xforce.ibmcloud.com/vulnerabilities/17415
https://bugzilla.mozilla.org/show_bug.cgi?id=252342
http://www.securityfocus.com/bid/11186
http://securitytracker.com/id?1011331
http://secunia.com/advisories/12580/
http://marc.info/?l=bugtraq&m=109536612321898&w=2
http://kuza55.blogspot.com/2008/02/understanding-cookie-security.html