Function at 0x40337d
Capabilities:
Accept command line arguments
Check os version
Copy file
Delete file
Get common file path
Get file system object information
Set current directory
Set environment variable
Shutdown system
Terminate process

Disassembly:
push ebp
mov ebp, esp
sub esp, 0x220
push esi
push edi
xor edi, edi
push 0x8001
mov dword [ebp - 0x10], edi
mov dword [ebp - 4], str.Error_writing_temporary_file._Make_sure_your_temp_folder_is_valid.
mov dword [ebp - 8], edi
mov byte [ebp - 0xc], 0x20
call dword [sym.imp.KERNEL32.dll_SetErrorMode]
mov esi, dword [sym.imp.KERNEL32.dll_GetVersionExA]
lea eax, [ebp - 0xc0]
push eax
mov dword [ebp - 0xac], edi
mov dword [ebp - 0x2c], edi
mov dword [ebp - 0x28], edi
mov dword [ebp - 0xc0], 0x9c
call esi
test eax, eax
jne 0x40340e
lea eax, [ebp - 0xc0]
mov dword [ebp - 0xc0], 0x94
push eax
call esi
cmp dword [ebp - 0xb0], 2
jne 0x403415
movsx cx, byte [ebp - 0x9f]
mov al, byte [ebp - 0xac]
sub ecx, 0x30
sub al, 0x53
mov byte [ebp - 0x26], 4
neg al
sbb eax, eax
not eax
and eax, ecx
mov word [ebp - 0x2c], ax
cmp dword [ebp - 0xb0], 2
jae 0x403439
and byte [ebp - 0x26], 0
cmp byte [ebp - 0xab], 0x41
jl 0x403435
movsx ax, byte [ebp - 0xab]
sub eax, 0x40
mov word [ebp - 0x2c], ax
jmp 0x403439
mov word [ebp - 0x2c], di
cmp dword [ebp - 0xbc], 0xa
jae 0x40344a
and word [ebp - 0xb2], 0
mov eax, dword [ebp - 0xb4]
movzx ecx, byte [ebp - 0xb8]
mov dword [0x4247d8], eax
xor eax, eax
mov ah, byte [ebp - 0xbc]
movzx eax, ax
or eax, ecx
xor ecx, ecx
mov ch, byte [ebp - 0x2c]
movzx ecx, cx
shl eax, 0x10
or eax, ecx
movzx ecx, byte [ebp - 0x26]
or eax, ecx
mov dword [0x4247dc], eax
cmp word [0x4247de], 0x600
je 0x40349d
push edi
call fcn.0040662d
cmp eax, edi
je 0x40349d
push 0xc00
call eax
mov esi, str.UXTHEME
push esi
call fcn.004065bf
push esi
call dword [sym.imp.KERNEL32.dll_lstrlenA]
lea esi, [esi + eax + 1]
cmp byte [esi], 0
jne 0x4034a2
push 0xb
call fcn.0040662d
push 9
call fcn.0040662d
push 7
mov dword [0x424724], eax
call fcn.0040662d
cmp eax, edi
je 0x4034e5
push 0x1e
call eax
test eax, eax
je 0x4034e5
or byte [0x4247dc], 0x80
push ebx
call dword [sym.imp.COMCTL32.dll_InitCommonControls]
push edi
call dword [sym.imp.ole32.dll_OleInitialize]
mov dword [0x4247e0], eax
push edi
lea eax, [ebp - 0x220]
push 0x160
push eax
push edi
push 0x41fce8
call dword [sym.imp.SHELL32.dll_SHGetFileInfoA]
push str.NSIS_Error
push 0x423f20
call fcn.00406221
call dword [sym.imp.KERNEL32.dll_GetCommandLineA]
mov ebx, 0x42a000
push eax
push ebx
call fcn.00406221
cmp byte [0x42a000], 0x22
mov dword [0x424720], 0x400000
mov eax, ebx
jne 0x403550
mov byte [ebp - 0xc], 0x22
mov eax, 0x42a001
push dword [ebp - 0xc]
push eax
call fcn.00405bde
push eax
call dword [sym.imp.USER32.dll_CharNextA]
mov dword [ebp - 0x14], eax
jmp 0x403624
cmp cl, 0x20
jne 0x403573
inc eax
cmp byte [eax], 0x20
je 0x40356d
cmp byte [eax], 0x22
mov byte [ebp - 0xc], 0x20
jne 0x403581
inc eax
mov byte [ebp - 0xc], 0x22
cmp byte [eax], 0x2f
jne 0x403615
inc eax
cmp byte [eax], 0x53
jne 0x4035a6
mov cl, byte [eax + 1]
cmp cl, 0x20
je 0x40359c
test cl, cl
jne 0x4035a6
mov dword [0x4247c0], 1
movsx ecx, byte [0x40a183]
movsx edx, byte [0x40a182]
shl ecx, 8
or ecx, edx
movsx edx, byte [0x40a181]
shl ecx, 8
or ecx, edx
movsx edx, byte [str.NCRC]
shl ecx, 8
or ecx, edx
cmp dword [eax], ecx
jne 0x4035e5
mov cl, byte [eax + 4]
cmp cl, 0x20
je 0x4035e1
test cl, cl
jne 0x4035e5
or dword [ebp - 8], 4
movsx ecx, byte [0x40a17b]
movsx edx, byte [0x40a17a]
shl ecx, 8
or ecx, edx
movsx edx, byte [0x40a179]
shl ecx, 8
or ecx, edx
movsx edx, byte [str.__D]
shl ecx, 8
or ecx, edx
cmp dword [eax - 2], ecx
je 0x403630
push dword [ebp - 0xc]
push eax
call fcn.00405bde
cmp byte [eax], 0x22
jne 0x403624
inc eax
mov cl, byte [eax]
test cl, cl
jne 0x403568
jmp 0x403642
and byte [eax - 2], 0
add eax, 2
push eax
push 0x42a400
call fcn.00406221
mov edi, dword [sym.imp.KERNEL32.dll_GetTempPathA]
mov esi, 0x42b400
push esi
push 0x400
call edi
call fcn.0040334c
test eax, eax
jne 0x4036b4
push 0x3fb
push esi
call dword [sym.imp.KERNEL32.dll_GetWindowsDirectoryA]
push str.Temp
push esi
call sub.KERNEL32.dll_lstrcatA
call fcn.0040334c
test eax, eax
jne 0x4036b4
push esi
push 0x3fc
call edi
push 0x40a16c
push esi
call sub.KERNEL32.dll_lstrcatA
mov edi, dword [sym.imp.KERNEL32.dll_SetEnvironmentVariableA]
push esi
push str.TEMP
call edi
push esi
push 0x40a160
call edi
call fcn.0040334c
test eax, eax
je 0x40375f
push 0x42b000
call dword [sym.imp.KERNEL32.dll_DeleteFileA]
push dword [ebp - 8]
call fcn.00402f0c
test eax, eax
mov dword [ebp - 4], eax
jne 0x40375f
cmp dword [0x42473c], eax
je 0x403750
push eax
push ebx
call fcn.00405bde
mov edi, eax
cmp edi, ebx
jb 0x40371b
movsx eax, byte [0x40a15b]
movsx ecx, byte [0x40a15a]
shl eax, 8
or eax, ecx
movsx ecx, byte [0x40a159]
shl eax, 8
or eax, ecx
movsx ecx, byte [str.___]
shl eax, 8
or eax, ecx
cmp dword [edi], eax
je 0x40371b
dec edi
cmp edi, ebx
jae 0x403712
cmp edi, ebx
mov dword [ebp - 4], str.Error_launching_installer
jb 0x40378b
and byte [edi], 0
add edi, 4
push edi
call fcn.00405ca1
test eax, eax
je 0x40375f
push edi
push 0x42a400
call fcn.00406221
push edi
push 0x42a800
call fcn.00406221
and dword [ebp - 4], 0
or dword [0x4247cc], 0xffffffff
call fcn.00403a07
mov dword [ebp - 0x10], eax
call fcn.0040392d
call dword [sym.imp.ole32.dll_OleUninitialize]
xor edi, edi
pop ebx
cmp dword [ebp - 4], edi
je 0x403899
push 0x200010
push dword [ebp - 4]
call fcn.00405937
push 2
call dword [sym.imp.KERNEL32.dll_ExitProcess]
call fcn.004058a2
push str.nsu
push esi
mov ebx, eax
call sub.KERNEL32.dll_lstrcatA
test ebx, ebx
je 0x4037ac
push 0x40a14c
push esi
call sub.KERNEL32.dll_lstrcatA
push str..tmp
push esi
call sub.KERNEL32.dll_lstrcatA
mov edi, 0x42ac00
push edi
push esi
call dword [sym.imp.KERNEL32.dll_lstrcmpiA]
test eax, eax
je 0x40375f
test ebx, ebx
push esi
je 0x4037d4
call fcn.00405808
jmp 0x4037d9
call fcn.00405885
push esi
call dword [sym.imp.KERNEL32.dll_SetCurrentDirectoryA]
cmp byte [0x42a400], 0
jne 0x4037f4
push edi
push 0x42a400
call fcn.00406221
push dword [ebp - 0x14]
push section..ndata
call fcn.00406221
movsx cx, byte [0x40a140]
xor eax, eax
mov dword [ebp - 8], 0x1a
mov ah, byte [0x40a141]
mov edi, 0x41f8e8
or eax, ecx
mov word [0x425400], ax
mov eax, dword [0x424730]
push dword [eax + 0x120]
push edi
call fcn.004062b4
push edi
call dword [sym.imp.KERNEL32.dll_DeleteFileA]
xor ebx, ebx
cmp dword [ebp - 4], ebx
je 0x403882
push 1
push edi
push 0x42bc00
call dword [sym.imp.KERNEL32.dll_CopyFileA]
test eax, eax
je 0x403882
push ebx
push edi
call fcn.00405ffa
mov eax, dword [0x424730]
push dword [eax + 0x124]
push edi
call fcn.004062b4
push edi
call fcn.004058ba
cmp eax, ebx
je 0x403882
push eax
call dword [sym.imp.KERNEL32.dll_CloseHandle]
mov dword [ebp - 4], ebx
inc byte [0x425400]
dec dword [ebp - 8]
jne 0x403825
push ebx
push esi
call fcn.00405ffa
jmp 0x40375f
cmp dword [0x4247b4], edi
je 0x403917
lea eax, [ebp - 0x14]
push eax
push 0x28
call dword [sym.imp.KERNEL32.dll_GetCurrentProcess]
push eax
call dword [sym.imp.ADVAPI32.dll_OpenProcessToken]
test eax, eax
je 0x4038e7
lea eax, [ebp - 0x20]
push eax
push str.SeShutdownPrivilege
push edi
call dword [sym.imp.ADVAPI32.dll_LookupPrivilegeValueA]
push edi
push edi
lea eax, [ebp - 0x24]
push edi
push eax
push edi
push dword [ebp - 0x14]
mov dword [ebp - 0x24], 1
mov dword [ebp - 0x18], 2
call dword [sym.imp.ADVAPI32.dll_AdjustTokenPrivileges]
push 4
call fcn.0040662d
cmp eax, edi
mov esi, 0x80040002
je 0x403903
push esi
push 0x25
push edi
push edi
push edi
call eax
test eax, eax
je 0x403910
push esi
push 2
call dword [sym.imp.USER32.dll_ExitWindowsEx]
test eax, eax
jne 0x403917
push 9
call fcn.0040140b
mov eax, dword [0x4247cc]
cmp eax, 0xffffffff
je 0x403924
mov dword [ebp - 0x10], eax
push dword [ebp - 0x10]
call dword [sym.imp.KERNEL32.dll_ExitProcess]