Summary
While installing Opera, if the "USE SEPARATE SETTINGS FOR EACH USER" option is selected, the "opera7/profile" folder is stored in the "<username>/application data/opera7" location instead of in the Opera root folder. The "profile" folder contains user specific data for different Opera users. Therefore, each user has a different "profile" folder in his "<username>/application data/opera7" folder.
Folders of interest to us in which configuration files are automatically downloaded and stored (like skin, toolbar, mouse, etc.) are subfolders of the "profile" folder and hence are also moved to this location.
In this scenario, the arbitrary files can still be dropped in the respective folders. However, for executing the files, the <username> variable must be known. Other methods of exploiting this scenario may come up later.
Details
Vulnerable systems:
* Opera version 7.21 and prior
Immune systems:
* Opera version 7.22
http://www.securiteam.com/exploits/6W00J2K8UI.html
Also - http://www.securiteam.com/windowsntfocus/6U00H2K8UY.html

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