Opera before 9.52, when rendering an http page that has loaded an https page into a frame, displays a padlock icon and offers a security information dialog reporting a secure connection, which might allow remote attackers to trick a user into performing unsafe actions on the http page.
Gentoo Linux Security Advisory GLSA 200811-01 - Multiple vulnerabilities have been discovered in Opera, allowing for the execution of arbitrary code. Versions below 9.62 are affected.