# Python implementation of the Trend Micro Password Decryptor # This script decrypts encrypted passwords stored in the TrendMicro OfficeScan "odscan.ini" file # # original code from https://aluigi.altervista.org/pwdrec.htm#trendmicropwd # original code was developed by Luigi Auriemma in the year of 2008 # # This script was ported to Python by Tamas Jos @skelsec # # TODO: the script is missing the trendmicro_PWDDecrypt function, which doesn't seem to be in use anymore from unicrypto.symmetric import AES, cipherMODE import array import os import re def trendmicro_build_key(pwd1, pwd2): o = [513,1027,1541,2055] pwd1 = [x for x in pwd1] pwd2 = [x for x in pwd2] idxa = 0 idxb = 0 a = pwd1[idxa] b = pwd2[idxb] x = 0x7f3b for i in range(4): if a == 0 and b == 0: break x ^= ((a | (b << 8)) ^ 0x6b2c) & 0xffff t = i if i==1: t = 2 elif i==2: t = 1 o[t] ^= (x & 0xffff) idxa += 1 idxb += 1 if idxa >= len(pwd1): a = 0 else: a = pwd1[idxa] if idxb >= len(pwd2): b = 0 else: b = pwd2[idxb] return b''.join([int.to_bytes(x, 2, byteorder='little', signed=False) for x in o]) def trendmicro_crypt(encdata:str): multistr = 0 results = [] while len(encdata) > 0: multistr += 1 tablex = [0] * 768 if encdata[0] == '!': encdata = encdata[1:] blocks = int(encdata[0]) blocklen = bytes.fromhex(encdata[1:3])[0] encdata = encdata[3:] key = trendmicro_build_key(b"Windows7621673NT", b"Virus3761267Trend") res = '' tablex = trendmicro_crypt1(tablex, key) for i in range(blocks): i =i*16 blockdata = bytes.fromhex(encdata[i:i+16]) res += trendmicro_crypt2(tablex, blockdata) res = res[:blocklen] encdata = encdata[blocks*16:] rescrc = int.from_bytes(bytes.fromhex(encdata[:8]), byteorder='big', signed=False) encdata = encdata[8:] # crc is taken over all 4 byte aligned blocks (not the last block if it's not aligned) crcblocklen = (blocklen//4)*4 crc = 0x4f627a3b x = array.array('I', res.encode()[:crcblocklen]) for c in x: crc = (crc ^ c) & 0xffffffff if crc != rescrc: res = '!!!CRC MISMATCH!!!' + res if multistr == 1: res = res[3:] results.append(res) return ''.join(results) def trendmicro_crypt2(tablex, blockdata, encdec:bool=False): table1 = b"\x07\x02\x06\x02\x05\x02\x04\x02\x03\x02\x02\x02\x01\x02\x00\x02" +\ b"\x07\x08\x06\x08\x05\x08\x04\x08\x03\x08\x02\x08\x01\x08\x00\x08" +\ b"\x07\x20\x06\x20\x05\x20\x04\x20\x03\x20\x02\x20\x01\x20\x00\x20" +\ b"\x07\x80\x06\x80\x05\x80\x04\x80\x03\x80\x02\x80\x01\x80\x00\x80" +\ b"\x07\x01\x06\x01\x05\x01\x04\x01\x03\x01\x02\x01\x01\x01\x00\x01" +\ b"\x07\x04\x06\x04\x05\x04\x04\x04\x03\x04\x02\x04\x01\x04\x00\x04" +\ b"\x07\x10\x06\x10\x05\x10\x04\x10\x03\x10\x02\x10\x01\x10\x00\x10" +\ b"\x07\x40\x06\x40\x05\x40\x04\x40\x03\x40\x02\x40\x01\x40\x00\x40" table2 = b"\x1f\x00\x01\x02\x03\x04\x03\x04\x05\x06\x07\x08\x07\x08\x09\x0a" +\ b"\x0b\x0c\x0b\x0c\x0d\x0e\x0f\x10\x0f\x10\x11\x12\x13\x14\x13\x14" +\ b"\x15\x16\x17\x18\x17\x18\x19\x1a\x1b\x1c\x1b\x1c\x1d\x1e\x1f\x00" table3 = b"\x0e\x04\x0d\x01\x02\x0f\x0b\x08\x03\x0a\x06\x0c\x05\x09\x00\x07" +\ b"\x00\x0f\x07\x04\x0e\x02\x0d\x01\x0a\x06\x0c\x0b\x09\x05\x03\x08" +\ b"\x04\x01\x0e\x08\x0d\x06\x02\x0b\x0f\x0c\x09\x07\x03\x0a\x05\x00" +\ b"\x0f\x0c\x08\x02\x04\x09\x01\x07\x05\x0b\x03\x0e\x0a\x00\x06\x0d" +\ b"\x0f\x01\x08\x0e\x06\x0b\x03\x04\x09\x07\x02\x0d\x0c\x00\x05\x0a" +\ b"\x03\x0d\x04\x07\x0f\x02\x08\x0e\x0c\x00\x01\x0a\x06\x09\x0b\x05" +\ b"\x00\x0e\x07\x0b\x0a\x04\x0d\x01\x05\x08\x0c\x06\x09\x03\x02\x0f" +\ b"\x0d\x08\x0a\x01\x03\x0f\x04\x02\x0b\x06\x07\x0c\x00\x05\x0e\x09" +\ b"\x0a\x00\x09\x0e\x06\x03\x0f\x05\x01\x0d\x0c\x07\x0b\x04\x02\x08" +\ b"\x0d\x07\x00\x09\x03\x04\x06\x0a\x02\x08\x05\x0e\x0c\x0b\x0f\x01" +\ b"\x0d\x06\x04\x09\x08\x0f\x03\x00\x0b\x01\x02\x0c\x05\x0a\x0e\x07" +\ b"\x01\x0a\x0d\x00\x06\x09\x08\x07\x04\x0f\x0e\x03\x0b\x05\x02\x0c" +\ b"\x07\x0d\x0e\x03\x00\x06\x09\x0a\x01\x02\x08\x05\x0b\x0c\x04\x0f" +\ b"\x0d\x08\x0b\x05\x06\x0f\x00\x03\x04\x07\x02\x0c\x01\x0a\x0e\x09" +\ b"\x0a\x06\x09\x00\x0c\x0b\x07\x0d\x0f\x01\x03\x0e\x05\x02\x08\x04" +\ b"\x03\x0f\x00\x06\x0a\x01\x0d\x08\x09\x04\x05\x0b\x0c\x07\x02\x0e" +\ b"\x02\x0c\x04\x01\x07\x0a\x0b\x06\x08\x05\x03\x0f\x0d\x00\x0e\x09" +\ b"\x0e\x0b\x02\x0c\x04\x07\x0d\x01\x05\x00\x0f\x0a\x03\x09\x08\x06" +\ b"\x04\x02\x01\x0b\x0a\x0d\x07\x08\x0f\x09\x0c\x05\x06\x03\x00\x0e" +\ b"\x0b\x08\x0c\x07\x01\x0e\x02\x0d\x06\x0f\x00\x09\x0a\x04\x05\x03" +\ b"\x0c\x01\x0a\x0f\x09\x02\x06\x08\x00\x0d\x03\x04\x0e\x07\x05\x0b" +\ b"\x0a\x0f\x04\x02\x07\x0c\x09\x05\x06\x01\x0d\x0e\x00\x0b\x03\x08" +\ b"\x09\x0e\x0f\x05\x02\x08\x0c\x03\x07\x00\x04\x0a\x01\x0d\x0b\x06" +\ b"\x04\x03\x02\x0c\x09\x05\x0f\x0a\x0b\x0e\x01\x07\x06\x00\x08\x0d" +\ b"\x04\x0b\x02\x0e\x0f\x00\x08\x0d\x03\x0c\x09\x07\x05\x0a\x06\x01" +\ b"\x0d\x00\x0b\x07\x04\x09\x01\x0a\x0e\x03\x05\x0c\x02\x0f\x08\x06" +\ b"\x01\x04\x0b\x0d\x0c\x03\x07\x0e\x0a\x0f\x06\x08\x00\x05\x09\x02" +\ b"\x06\x0b\x0d\x08\x01\x04\x0a\x07\x09\x05\x00\x0f\x0e\x02\x03\x0c" +\ b"\x0d\x02\x08\x04\x06\x0f\x0b\x01\x0a\x09\x03\x0e\x05\x00\x0c\x07" +\ b"\x01\x0f\x0d\x08\x0a\x03\x07\x04\x0c\x05\x06\x0b\x00\x0e\x09\x02" +\ b"\x07\x0b\x04\x01\x09\x0c\x0e\x02\x00\x06\x0a\x0d\x0f\x03\x05\x08" +\ b"\x02\x01\x0e\x07\x04\x0a\x08\x0d\x0f\x0c\x09\x00\x03\x05\x06\x0b" table4 = b"\x0f\x06\x13\x14\x1c\x0b\x1b\x10\x00\x0e\x16\x19\x04\x11\x1e\x09" +\ b"\x01\x07\x17\x0d\x1f\x1a\x02\x08\x12\x0c\x1d\x05\x15\x0a\x03\x18" table5 = b"\x27\x07\x2f\x0f\x37\x17\x3f\x1f\x26\x06\x2e\x0e\x36\x16\x3e\x1e" +\ b"\x25\x05\x2d\x0d\x35\x15\x3d\x1d\x24\x04\x2c\x0c\x34\x14\x3c\x1c" +\ b"\x23\x03\x2b\x0b\x33\x13\x3b\x1b\x22\x02\x2a\x0a\x32\x12\x3a\x1a" +\ b"\x21\x01\x29\x09\x31\x11\x39\x19\x20\x00\x28\x08\x30\x10\x38\x18" tmp = [0] * 0x60 tmp2 = [0] * 0x30 bck = [0] * 0x20 for i in range(0x40): tmp[i] = 1 if (blockdata[table1[i * 2]] & table1[(i * 2) + 1]) else 0 for i in range(0x10): bck = tmp[0x20:0x40] if encdec is True: t = i else: t = 0xf - i for j in range(0x30): tmp2[j] = tmp[0x20 + table2[j]] ^ tablex[(t * 0x30) + j] for j in range(8): t = j*6 c = (tmp2[t] << 5) | (tmp2[t + 1] << 3) | (tmp2[t + 2] << 2) | (tmp2[t + 3] << 1) | tmp2[t + 4] | (tmp2[t + 5] << 4) c = table3[(j << 6) + c] t = j << 2 tmp[0x40 + t] = (c >> 3) & 1 tmp[0x41 + t] = (c >> 2) & 1 tmp[0x42 + t] = (c >> 1) & 1 tmp[0x43 + t] = c & 1 for j in range(0x20): tmp[0x20 + j] = tmp[j] ^ tmp[0x40 + table4[j]] tmp = bck + tmp[0x20:] bck = tmp[0x20:0x40] tmp = tmp[:0x20] + tmp[:0x20] + tmp[0x40:] tmp = bck + tmp[0x20:] tdata = [x for x in blockdata] t = 0 for i in range(8): tdata[i] = 0 j = 1 while j <= 0x80: if tmp[table5[t]]: tdata[i] |= j t += 1 j = j*2 tdata = ''.join(chr(x) for x in tdata) return tdata def trendmicro_crypt1(tablex, key): table1 = b"\x07\x01\x06\x01\x05\x01\x04\x01\x03\x01\x02\x01\x01\x01\x00\x01" +\ b"\x07\x02\x06\x02\x05\x02\x04\x02\x03\x02\x02\x02\x01\x02\x00\x02" +\ b"\x07\x04\x06\x04\x05\x04\x04\x04\x03\x04\x02\x04\x01\x04\x00\x04" +\ b"\x07\x08\x06\x08\x05\x08\x04\x08\x07\x40\x06\x40\x05\x40\x04\x40" +\ b"\x03\x40\x02\x40\x01\x40\x00\x40\x07\x20\x06\x20\x05\x20\x04\x20" +\ b"\x03\x20\x02\x20\x01\x20\x00\x20\x07\x10\x06\x10\x05\x10\x04\x10" +\ b"\x03\x10\x02\x10\x01\x10\x00\x10\x03\x08\x02\x08\x01\x08\x00\x08" table2 = b"\x01\x01\x02\x02\x02\x02\x02\x02\x01\x02\x02\x02\x02\x02\x02\x01" table3 = b"\x0d\x10\x0a\x17\x00\x04\x02\x1b\x0e\x05\x14\x09\x16\x12\x0b\x03" +\ b"\x19\x07\x0f\x06\x1a\x13\x0c\x01\x28\x33\x1e\x24\x2e\x36\x1d\x27" +\ b"\x32\x2c\x20\x2f\x2b\x30\x26\x37\x21\x34\x2d\x29\x31\x23\x1c\x1f" tmp = [0] * 0x38 for i in range(0x38): kl = key[table1[i * 2]] tl = table1[(i * 2) + 1] kt = kl & tl tmp[i] = 1 if kt else 0 c = 0 for i in range(0x10): c += table2[i] for j in range(0x30): t = table3[j] if t < 0x1C: r = 0 else: r = 0x1C t -= 0x1C t += c if t >= 0x1C: t -= 0x1C t += r tablex[(i * 0x30) + j] = tmp[t] return tablex def trendmicro_cryptex(encdata:str): # static AES key and IV # security is top notch key = b"\xeb\x06\xe9\xc7\x6c\x16\x1d\x6c\x89\x70\x3d\xfc\x72\x53\xff\xdd\x71\xad\x07\xbf\x12\xf4\xa2\xe7\xa0\x89\xfc\x7c\xa6\xca\x4b\x73" iv = b"\x15\x69\x2e\xfc\x39\x89\x4a\xba\x9b\x62\xce\x66\xc9\x05\x12\xae" dec = AES(key, cipherMODE.CBC, iv).decrypt(bytes.fromhex(encdata)) # remove pkcs1 padding from decrypted data dec = dec[:-dec[-1]] return dec[3:].decode('utf-8') def trendmicro_decrypt(encdata:str): if encdata.startswith('!CRYPT!') is True: return trendmicro_crypt(encdata[7:]) if encdata.startswith('!CRYPTEX!') is True: return trendmicro_cryptex(encdata[9:]) if encdata.startswith('!CRYPTEX3!') is True: return trendmicro_cryptex(encdata[10:]) if encdata.startswith('!CRYPTNG!') is True: return 'Decrypting CRYPTNG is not supported' def parse_ofscan_ini_file(filepath): pattern = re.compile(r'^([^=]+?)=\s*((!CRYPTEX!|!CRYPT!|!CRYPTEX3!|!CRYPTNG!)[^=]+)$') result = [] with open(filepath, 'r', encoding='latin-1') as f: for line in f: line = line.strip() if line == '': continue match = pattern.match(line) if match: result.append((match.group(1), match.group(2))) return result def ofscan_decrypt_data(filepath_or_data): if os.path.isfile(filepath_or_data): lines = parse_ofscan_ini_file(filepath_or_data) else: lines = ['RESULT:', filepath_or_data] results = [] for line in lines: try: decdata = trendmicro_decrypt(line[1]) if decdata is None: continue if decdata.startswith('!CRYPTEX!') is True: decdata = trendmicro_decrypt(decdata) results.append((line[0], decdata)) except Exception as e: results.append((line[0], 'Failed to decrypt: %s Reason: %s' % (line[1], e))) return results def main(): import argparse parser = argparse.ArgumentParser(description='Decrypt TrendMicro ofscan.ini file') parser.add_argument('filepath', help='ofscan.ini file path or string beginning with !CRYPT! or !CRYPTEX! or !CRYPTEX3!') args = parser.parse_args() results = ofscan_decrypt_data(args.filepath) for result in results: print('%s: %s' % (result[0], result[1])) if __name__ == '__main__': main()