Mozilla 0.9.6 and earlier and Netscape 6.2 and earlier allows remote attackers to steal cookies from another domain via a link with a hex-encoded null character (%00) followed by the target domain.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2002-1992
http://www.securityfocus.com/bid/3925
http://www.iss.net/security_center/static/7973.php
http://archives.neohapsis.com/archives/bugtraq/2002-01/0270.html
http://alive.znep.com/~marcs/security/mozillacookie/demo.html