I guess I'm glad Adobe are so open about how security can (I'm guessing) be breached with Flash. See more:
7.3 Local Storage. Flash Player and Adobe AIR may allow third parties to store certain information on your Computer in a local data file known as a local shared object. The type and amount of information that the third party application requests to be stored in a local shared object can vary by application and such requests are solely controlled by the third party. You can find more information on local shared objects at http://www.adobe.com/go/flashplayer_security. For more information on how to limit or control the storage of local shared objects on your Computer, please visit http://www.adobe.com/go/settmgr_storage_en.
Now, what is with the incredibly long document with no language menu so one has to scroll through searching for your own language?