# ReadFile(eax, &esp+80, 0x50, &esp+8, 0)
code += x86.Lea("EBX", x86.mem("[ESP + 0x80]"))
code += x86.Push(0)
code += x86.Push("EDI")
code += x86.Push(0xF0) # Oops stack overflow
code += x86.Push("EBX")
code += x86.Push("EAX") # hConsoleInput
code += x86.Call(call_import(imports["kernel32.dll"]["ReadFile"]))
# GetStdHandle(STD_OUTPUT_HANDLE)
code += x86.Push(STD_OUTPUT_HANDLE)
code += x86.Call(call_import(imports["kernel32.dll"]["GetStdHandle"]))
# WriteFile(eax, &esp+50, 0x50, &esp+8, 0)
code += x86.Push(0)
code += x86.Push("EDI")
code += x86.Push(0x50)
code += x86.Push("EBX")
code += x86.Push("EAX") # hConsoleOutput
code += x86.Call(call_import(imports["kernel32.dll"]["WriteFile"]))
code += x86.Mov("ESP", "EBP")
code += x86.Ret()
padded_code = code.get_code()
padded_code += x86.Nop().get_code() * (0x100 - len(padded_code))
section_text.content = tobytes(padded_code)
builder = PE.Builder(binary32)
builder.build_imports(True)
builder.build()
builder.write("pwn.exe")
print("Generated pwn.exe")
def build_pe_executable(asm_code: bytearray,
memory_layout: List[MemorySection],
arch: Architecture) -> str:
"""
Uses LIEF to build a standalone binary.
Upon success, return the path to the file generated
"""
if not is_x86_32(arch) and not is_x86_64(arch):
raise ValueError("Unsupported architecture for PE generation")
is_x64 = is_x86_64(arch)
if is_x64:
basename = "cemu-pe-amd64-{:s}".format(generate_random_string(5))
pe = PE.Binary(basename, PE.PE_TYPE.PE32_PLUS)
else:
basename = "cemu-pe-i386-{:s}".format(generate_random_string(5))
pe = PE.Binary(basename, PE.PE_TYPE.PE32)
# adding sections
sections = {}
reladdr = 0x1000
for mem in memory_layout:
name, base_address, size, permission = mem.name, mem.address, mem.size, mem.permission
if name in (".stack", ):
continue
sect = PE.Section(name)
if name == ".text":
# .text section: copy our code and set the entrypoint to the
# beginning VA
sect.content = asm_code
sect.virtual_address = reladdr
sect.characteristics = parse_as_lief_pe_permission(
permission, "code")
sections["text"] = pe.add_section(sect, PE.SECTION_TYPES.TEXT)
elif name == ".data":
# .data is also sure to exist
sect.content = b"\x00"
sect.virtual_address = reladdr
sect.characteristics = parse_as_lief_pe_permission(
permission, "udata")
sections["data"] = pe.add_section(sect, PE.SECTION_TYPES.DATA)
reladdr += size
# fixing pe header
pe.header.add_characteristic(PE.HEADER_CHARACTERISTICS.EXECUTABLE_IMAGE)
pe.header.add_characteristic(PE.HEADER_CHARACTERISTICS.DEBUG_STRIPPED)
if is_x64:
pe.header.add_characteristic(
PE.HEADER_CHARACTERISTICS.LARGE_ADDRESS_AWARE)
else:
pe.header.add_characteristic(
PE.HEADER_CHARACTERISTICS.CHARA_32BIT_MACHINE)
# fixing pe optional header
pe.optional_header.addressof_entrypoint = sections["text"].virtual_address
pe.optional_header.major_operating_system_version = 0x04
pe.optional_header.minor_operating_system_version = 0x00
pe.optional_header.major_subsystem_version = 0x05
pe.optional_header.minor_subsystem_version = 0x02
pe.optional_header.major_linker_version = 0x02
pe.optional_header.minor_linker_version = 0x1e
pe.optional_header.remove(PE.DLL_CHARACTERISTICS.NX_COMPAT)
pe.optional_header.add(PE.DLL_CHARACTERISTICS.NO_SEH)
# pe.add_library("ntdll.dll")
#building exe to disk
outfile = f"{tempfile.gettempdir()}{os.path.sep:s}{basename:s}.exe"
builder = PE.Builder(pe)
builder.build_imports(True)
builder.build()
builder.write(outfile)
return outfile
