Opera before 11.65 does not ensure that the address field corresponds to the displayed web page during unusually timed changes to this field, which makes it easier for user-assisted remote attackers to conduct spoofing attacks via vectors involving navigation, reloads, and redirects.

Opera before 12.00 Beta allows user-assisted remote attackers to cause a denial of service (application crash) via a crafted web page that is not properly handled during a reload, as demonstrated by a "multiple origin camera test" page.

Opera before 12.00 Beta allows remote attackers to cause a denial of service (application hang) via an absolutely positioned wrap=off TEXTAREA element located next to an "overflow: auto" block element.