Multiple vulnerabilities have been reported in Opera, which can be exploited by malicious people to conduct spoofing attacks and bypass certain security restrictions.

1) An error when displaying preferences within a small window can be exploited to e.g. execute arbitrary code by tricking a user into entering a specific keyboard sequence.

2) An error when displaying pop-up windows can be exploited to execute script code by tricking a user into following a specific sequence of events.

3) An error when handling JSON resources can be exploited to bypass the cross-domain policy restriction and disclose certain information to other sites.

4) An unspecified error can be exploited to display arbitrary content while showing the URL of a trusted web site in the address bar.

5) An error when handling page loads can be exploited to display arbitrary content while showing the URL of a trusted web site in the address bar.

Solution
Upgrade to version 12 or update to version 11.65 for Mac.

Provided and/or discovered by
1, 2, 4) The vendor credits Jordi Chancel
3) Reported by the vendor
5) Code Audit Labs

Changelog
Further details available to Secunia VIM customers

Original Advisory
Opera:
http://www.opera.com/docs/changelogs/windows/1200/
http://www.opera.com/docs/changelogs/unix/1200/

Code Audit Labs:
http://blog.vulnhunt.com/index.php/2012/06/14/cal-2012-0015-opera-website-spoof/

Deep Links
Links available to Secunia VIM customers