Integer overflow in Opera 8.54 and earlier allows remote attackers to execute arbitrary code via a JPEG image with large height and width values, which causes less memory to be allocated than intended.

Integer signedness error in Opera before 8.54 allows remote attackers to execute arbitrary code via long values in a stylesheet attribute, which pass a length check. NOTE: a sign extension problem makes the attack easier with shorter strings.

Opera 8.02 and earlier allows remote attackers to cause a denial of service (client crash) via (1) a crafted HTML file with a "content: url(0);" style attribute, a "bodyA" tag, a long string, and a "u" tag with a long attribute, as demonstrated by opera.html; and (2) a BGSOUND element with a "margin:-99;" STYLE attribute.

Opera before 8.51, when running on Windows with Input Method Editor (IME) installed, allows remote attackers to cause a denial of service (persistent application crash) by bookmarking a site with a long title.

Opera before 8.51 on Linux and Unix systems allows remote attackers to execute arbitrary code via shell metacharacters (backticks) in a URL that another product provides in a command line argument when launching Opera.

Unspecified "drag-and-drop vulnerability" in Opera Web Browser before 8.50 on Windows allows "unintentional file uploads."

The mail client in Opera before 8.50 opens attached files from the user's cache directory without warning the user, which might allow remote attackers to inject arbitrary web script and spoof attachment filenames.

Opera before 8.50 allows remote attackers to spoof the content type of files via a filename with a trailing "." (dot), which might allow remote attackers to trick users into processing dangerous content.

A design error in Opera 8.01 and earlier allows user-assisted attackers to execute arbitrary code by overlaying a malicious new window above a file download dialog box, then tricking the user into double-clicking on the "Run" button, aka "link hijacking".

Opera 7.x and 8 before 8.01 does not clearly associate a Javascript dialog box with the web page that generated it, which allows remote attackers to spoof a dialog box from a trusted site and facilitates phishing attacks, aka the "Dialog Origin Spoofing Vulnerability."

The XMLHttpRequest object in Opera 8.0 Final Build 1095 allows remote attackers to bypass access restrictions and perform unauthorized actions on other domains via a redirect.

Cross-site scripting (XSS) vulnerability in Opera 8.0 Final Build 1095 allows remote attackers to inject arbitrary web script or HTML via "javascript:" URLs when a new window or frame is opened, which allows remote attackers to bypass access restrictions and perform unauthorized actions on other domains.