The confirm_create_account function in the account-creation feature in token.cgi in Bugzilla 2.x through 4.0.x before 4.0.15, 4.1.x and 4.2.x before 4.2.11, 4.3.x and 4.4.x before 4.4.6, and 4.5.x before 4.5.6 does not specify a scalar context for the realname parameter, which allows remote attackers to create accounts with unverified e-mail addresses by sending three realname values with realname=login_name as the second, as demonstrated by selecting an e-mail address with a domain name for which group privileges are automatically granted.
https://security.gentoo.org/glsa/201607-11
https://bugzilla.mozilla.org/show_bug.cgi?id=1074812
http://www.securitytracker.com/id/1030978
http://www.reddit.com/r/netsec/comments/2ihen0/new_class_of_vulnerability_in_perl_web/
http://www.opennet.ru/opennews/art.shtml?num=40766
http://www.mandriva.com/security/advisories?name=MDVSA-2014:200
http://www.bugzilla.org/security/4.0.14/
http://packetstormsecurity.com/files/128578/Bugzilla-Account-Creation-XSS-Information-Leak.html
http://openwall.com/lists/oss-security/2014/10/07/20
http://lists.fedoraproject.org/pipermail/package-announce/2014-October/141321.html
http://lists.fedoraproject.org/pipermail/package-announce/2014-October/141309.html
http://lists.fedoraproject.org/pipermail/package-announce/2014-November/142524.html
http://blog.gerv.net/2014/10/new-class-of-vulnerability-in-perl-web-applications/