Buffer overflow in the SockPrintf function in wu-ftpd 2.6.2 and earlier, when compiled with MAIL_ADMIN option enabled on a system that supports very long pathnames, might allow remote anonymous users to execute arbitrary code by uploading a file with a long pathname, which triggers the overflow when wu-ftpd constructs a notification message to the administrator.

Successful exploitation requires that the option "MAIL_ADMIN" has been enabled (not default), that anonymous users have write permissions on a folder, and that the program has been compiled on a system where very long paths are permitted.