The offer_account_by_email function in User.pm in the WebService for Bugzilla before 3.0.2, and 3.1.x before 3.1.2, does not check the value of the createemailregexp parameter, which allows remote attackers to bypass intended restrictions on account creation.
fedoranews.org/updates/FEDORA-2007-229.shtml
secunia.com/advisories/26848
secunia.com/advisories/26969
www.bugzilla.org/security/3.0.1/
www.securityfocus.com/archive/1/480077/100/0/threaded
www.securityfocus.com/bid/25725
www.securitytracker.com/id?1018719
www.vupen.com/english/advisories/2007/3200
bugzilla.mozilla.org/show_bug.cgi?id=395632
bugzilla.redhat.com/show_bug.cgi?id=299981
exchange.xforce.ibmcloud.com/vulnerabilities/36692