Function at 0x48bc20
Capabilities:
Get file size
Get session user name
Write file on windows

Disassembly:
sub esp, 0x46c
push ebx
push ebp
push esi
mov esi, dword [sym.imp.KERNEL32.dll_EnterCriticalSection]
push edi
push 0x4d6b68
call esi
mov ecx, dword [esp + 0x480]
lea eax, [esp + 0x484]
push eax
push ecx
lea edx, [esp + 0x284]
push 0x200
push edx
call fcn.0048cd17
or ebp, 0xffffffff
lea edi, [esp + 0x28c]
mov ecx, ebp
xor eax, eax
add esp, 0x10
mov byte [esp + 0x47b], 0
repne scasb al, byte es:[edi]
mov eax, dword [0x4d6e0c]
not ecx
dec ecx
mov ebx, ecx
add eax, ebx
mov dword [esp + 0x10], ebx
cmp eax, 0x1000
jbe 0x48be74
push 0x4d6b68
call esi
mov eax, dword [0x4d6e0c]
xor esi, esi
cmp eax, esi
je 0x48be69
cmp dword [0x4aae94], ebp
jne 0x48be43
cmp dword [0x4aae90], esi
je 0x48bd35
lea ecx, [esp + 0x178]
push ecx
call fcn.0048c170
add esp, 4
lea edx, [esp + 0x14]
lea eax, [esp + 0x20]
mov dword [esp + 0x14], 0x20
push edx
push eax
call dword [sym.imp.ADVAPI32.dll_GetUserNameA]
test eax, eax
jne 0x48bce9
mov byte [esp + 0x20], al
lea ecx, [esp + 0x40]
push ecx
call fcn.0048bb50
mov eax, dword [esp + 0x58]
add esp, 4
mov edx, eax
lea ecx, [esp + 0x20]
and edx, 0xffff
shr eax, 0x10
push edx
push eax
mov eax, dword [esp + 0x58]
lea edx, [esp + 0x180]
and eax, 0xffff
push eax
push ecx
push edx
push str._s_s_02u_02u_02u.ERR
push 0x104
push 0x4d6d04
call fcn.00489aa0
add esp, 0x20
mov ecx, dword [0x4aae90]
xor ebx, ebx
cmp ecx, esi
sete bl
cmp ebx, 2
jge 0x48be15
push 0
push pe_nt_image_headers32
push 4
push 0
push 1
push 0x40000000
push 0x4d6d04
call dword [sym.imp.KERNEL32.dll_CreateFileA]
mov ebp, eax
cmp ebp, 0xffffffff
jne 0x48bdfe
push 0x5c
push 0x4d6d04
call fcn.0047c8d0
mov edx, eax
add esp, 8
test edx, edx
jne 0x48bd8d
mov edx, 0x4d6d04
mov eax, dword [0x4aae98]
mov ecx, 0x40
mov dword [esp + 0x74], eax
xor eax, eax
lea edi, [esp + 0x78]
lea esi, [esp + 0x74]
rep stosd dword es:[edi], eax
mov edi, edx
or ecx, 0xffffffff
repne scasb al, byte es:[edi]
not ecx
mov eax, esi
sub edi, ecx
mov esi, edi
mov edx, ecx
mov edi, eax
or ecx, 0xffffffff
xor eax, eax
repne scasb al, byte es:[edi]
mov ecx, edx
dec edi
shr ecx, 2
rep movsd dword es:[edi], dword [esi]
mov ecx, edx
and ecx, 3
rep movsb byte es:[edi], byte [esi]
lea edi, [esp + 0x74]
or ecx, 0xffffffff
repne scasb al, byte es:[edi]
not ecx
sub edi, ecx
mov edx, ecx
mov esi, edi
mov edi, 0x4d6d04
shr ecx, 2
rep movsd dword es:[edi], dword [esi]
mov ecx, edx
and ecx, 3
inc ebx
cmp ebx, 2
rep movsb byte es:[edi], byte [esi]
jl 0x48bd4b
jmp 0x48be15
push 0
push ebp
call dword [sym.imp.KERNEL32.dll_GetFileSize]
cmp eax, 0x10000
jbe 0x48be15
push ebp
call dword [sym.imp.KERNEL32.dll_SetEndOfFile]
xor esi, esi
cmp ebp, 0xffffffff
mov dword [0x4aae90], esi
mov dword [0x4aae94], ebp
jne 0x48be34
mov ebx, dword [esp + 0x10]
mov dword [0x4d6e0c], esi
jmp 0x48be74
push 2
push esi
push esi
push ebp
call dword [sym.imp.KERNEL32.dll_SetFilePointer]
mov ebx, dword [esp + 0x10]
mov ecx, dword [0x4d6e0c]
mov edx, dword [0x4d6e08]
lea eax, [esp + 0x1c]
push esi
push eax
mov eax, dword [0x4aae94]
push ecx
push edx
push eax
call dword [sym.imp.KERNEL32.dll_WriteFile]
mov dword [0x4d6e0c], esi
push 0x4d6b68
call dword [sym.imp.KERNEL32.dll_LeaveCriticalSection]
mov eax, dword [0x4d6e08]
test eax, eax
jne 0x48bea3
push 4
push 0x1000
push 0x1000
push eax
call dword [sym.imp.KERNEL32.dll_VirtualAlloc]
test eax, eax
mov dword [0x4d6e08], eax
mov dword [0x4d6e0c], 0
je 0x48bec9
mov edx, dword [0x4d6e0c]
mov ecx, ebx
lea esi, [esp + 0x27c]
lea edi, [eax + edx]
mov eax, ecx
shr ecx, 2
rep movsd dword es:[edi], dword [esi]
mov ecx, eax
and ecx, 3
rep movsb byte es:[edi], byte [esi]
add dword [0x4d6e0c], ebx
push 0x4d6b68
call dword [sym.imp.KERNEL32.dll_LeaveCriticalSection]
pop edi
pop esi
pop ebp
pop ebx
add esp, 0x46c
ret