Opera Cross Domain Scripting Vulnerability



Date Discovered

February 4, 2003


A vulnerability has been reported reported for Opera 7 browsers for Microsoft Windows operating systems. Due to flaws in Opera, it is possible for functions in different domains to be accessed and executed by an attacker with the credentials of the victim user. This vulnerability is also exacerbated by the fact that an attacker may also be able to override properties and methods in other windows to create malicious methods that will be accessed by a victim user. Exploitation of this vulnerability will allow an attacker to obtain access to local resources on a vulnerable system.

Technologies Affected

  • Opera Software Opera Web Browser 7.0.0 win32


Run all software as a nonprivileged user with minimal access rights.
Perform trivial tasks, such as browsing the Web, as a user with minimal privileges. This may reduce the consequences of successful exploitation.

Do not follow links provided by unknown or untrusted sources.
Some links may be obfuscated to redirect a user to a malicious site; be extremely cautious before following links provided by unknown sources.

Set web browser security to disable the execution of script code or active content.
Configure Opera to disable JavaScript as this will prevent exploitation of this vulnerability.

Opera Software has reportedly addressed this issue in Opera 7.01 for Windows.



Discovery of these vulnerabilities credited to GreyMagic Software.

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