Opera before 11.62 does not ensure that a dialog window is placed on top of content windows, which makes it easier for user-assisted remote attackers to trick users into downloading and executing arbitrary files via a download dialog located under other windows.
https://exchange.xforce.ibmcloud.com/vulnerabilities/74503
http://www.opera.com/support/kb/view/1011/
http://www.opera.com/docs/changelogs/windows/1162/
http://www.opera.com/docs/changelogs/unix/1162/
http://www.opera.com/docs/changelogs/mac/1162/
http://secunia.com/advisories/48535
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00012.html