byshell v0.64,用户态实现无进程无DLL无硬盘文件无启动项的后门程序。利用线程注射DLL到系统进程，解除DLL映射并删除自身文件和启动项，关机时恢复。-byshell v0.64, user-state-free process, no DLL files without the hard disk to start non-backdoor entry. DLL injection using a thread to the system process, the lifting map and delete the DLL files and start their own entries, shutdown resume.