The Serv-U File Server supports site specific commands which may not be universally supported by all FTP clients. Among these is the SITE EXEC command which allows a user to execute programs and scripts remotely, if the execute permission is present on the folder where a given program / script resides. A command injection vulnerability exists in this functionality due to improper sanitization of user-supplied parameters provided to the ShellExecuteExW routine. Successful exploitation results in arbitrary command execution under the context of the file server.
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