Opera before 11.50 does not properly restrict data: URIs, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via a crafted web site.
https://exchange.xforce.ibmcloud.com/vulnerabilities/68322
http://www.securityfocus.com/bid/48500
http://www.opera.com/support/kb/view/995/
http://www.opera.com/docs/changelogs/windows/1150/
http://www.opera.com/docs/changelogs/unix/1150/