Eudora (on Windows) has a feature called LaunchProtect, it is used to warn the user before running executable attachments. However this only works in the attach folder; using spoofed attachments, executables stored elsewhere may run without warning. In some setups, even executables in the attach folder may run without warning.
Vulnerable systems:
* Eudora version 6.0.1
http://www.securiteam.com/windowsntfocus/6G00P1P8UY.html

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