Opera 7.x up to 7.54, and possibly other versions, allows remote attackers to spoof arbitrary web sites by injecting content from one window into a target window whose name is known but resides in a different domain, as demonstrated using a pop-up window on a trusted web site, aka the "window injection" vulnerability.

Opera 7.54 and earlier allows remote attackers to spoof file types in the download dialog via dots and non-breaking spaces (ASCII character code 160) in the (1) Content-Disposition or (2) Content-Type headers.

The Javascript engine in Opera 7.23 allows remote attackers to cause a denial of service (crash) by creating a new Array object with a large size value, then writing into that array.

Opera 7.54 and earlier does not properly limit an applet's access to internal Java packages from Sun, which allows remote attackers to gain sensitive information, such as user names and the installation directory.

Opera offers an Open button to verify that a user wishes to execute a downloaded file, which allows user-assisted remote attackers to construct a race condition that tricks a user into clicking Open via a request for a different mouse or keyboard action very shortly before the Open dialog appears. NOTE: this is a different issue than CVE-2005-2407.

Opera Browser 7.23, and other versions before 7.50, updates the address bar as soon as the user clicks a link, which allows remote attackers to redirect to other sites via the onUnload attribute.

Opera 7.54 and earlier uses kfmclient exec to handle unknown MIME types, which allows remote attackers to execute arbitrary code via a shortcut or launcher that contains an Exec entry.

A race condition in Opera web browser 7.53 Build 3850 causes Opera to fill in the address bar before the page has been loaded, which allows remote attackers to spoof the URL in the address bar via the window.open and location.replace HTML parameters, which facilitates phishing attacks.

Opera before 7.54 allows remote attackers to modify properties and methods of the location object and execute Javascript to read arbitrary files from the client's local filesystem or display a false URL to the user.

Opera allows remote attackers to cause a denial of service (invalid memory reference and application crash) via a web page or HTML email that contains a TBODY tag with a large COL SPAN value, as demonstrated by mangleme.