Opera before 10.01 on Windows does not prevent use of Web fonts in rendering the product's own user interface, which allows remote attackers to spoof the address field via a crafted web site.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6384
https://exchange.xforce.ibmcloud.com/vulnerabilities/54022
https://euvd.enisa.europa.eu/vulnerability/EUVD-2009-3803
http://www.vupen.com/english/advisories/2009/3073
http://www.securityfocus.com/bid/36850
http://www.opera.com/support/kb/view/940/