Microsoft Windows MS17-010 SMB Remote Code Execution

This Metasploit module uses information disclosure to determine if MS17-010 has been patched or not. Specifically, it connects to the IPC$ tree and attempts a transaction on FID 0. If the status returned is "STATUS_INSUFF_SERVER_RESOURCES", the machine does not have the MS17-010 patch. This Metasploit module does not require valid SMB credentials in default server configurations. It can log on as the user "\" and connect to IPC$.


MD5 | 89159784c9ed66494a7cec42e5285517

##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

# auxiliary/scanner/smb/smb_ms_17_010

require 'msf/core'

class MetasploitModule < Msf::Auxiliary

include Msf::Exploit::Remote::SMB::Client
include Msf::Exploit::Remote::SMB::Client::Authenticated

include Msf::Auxiliary::Scanner
include Msf::Auxiliary::Report

def initialize(info = {})
super(update_info(info,
'Name' => 'MS17-010 SMB RCE Detection',
'Description' => %q{
Uses information disclosure to determine if MS17-010 has been patched or not.
Specifically, it connects to the IPC$ tree and attempts a transaction on FID 0.
If the status returned is "STATUS_INSUFF_SERVER_RESOURCES", the machine does
not have the MS17-010 patch.

This module does not require valid SMB credentials in default server
configurations. It can log on as the user "\" and connect to IPC$.
},
'Author' => [ 'Sean Dillon <[email protected]>' ],
'References' =>
[
[ 'CVE', '2017-0143'],
[ 'CVE', '2017-0144'],
[ 'CVE', '2017-0145'],
[ 'CVE', '2017-0146'],
[ 'CVE', '2017-0147'],
[ 'CVE', '2017-0148'],
[ 'MSB', 'MS17-010'],
[ 'URL', 'https://technet.microsoft.com/en-us/library/security/ms17-010.aspx']
],
'License' => MSF_LICENSE
))
end

def run_host(ip)
begin
status = do_smb_probe(ip)

if status == "STATUS_INSUFF_SERVER_RESOURCES"
print_warning("Host is likely VULNERABLE to MS17-010!")
report_vuln(
host: ip,
name: self.name,
refs: self.references,
info: 'STATUS_INSUFF_SERVER_RESOURCES for FID 0 against IPC$'
)
elsif status == "STATUS_ACCESS_DENIED" or status == "STATUS_INVALID_HANDLE"
# STATUS_ACCESS_DENIED (Windows 10) and STATUS_INVALID_HANDLE (others)
print_good("Host does NOT appear vulnerable.")
else
print_bad("Unable to properly detect if host is vulnerable.")
end

rescue ::Interrupt
print_status("Exiting on interrupt.")
raise $!
rescue ::Rex::Proto::SMB::Exceptions::LoginError
print_error("An SMB Login Error occurred while connecting to the IPC$ tree.")
rescue ::Exception => e
vprint_error("#{e.class}: #{e.message}")
ensure
disconnect
end
end

def do_smb_probe(ip)
connect

# logon as user \
simple.login(datastore['SMBName'], datastore['SMBUser'], datastore['SMBPass'], datastore['SMBDomain'])

# connect to IPC$
ipc_share = "\\\\#{ip}\\IPC$"
simple.connect(ipc_share)
tree_id = simple.shares[ipc_share]

print_status("Connected to #{ipc_share} with TID = #{tree_id}")

# request transaction with fid = 0
pkt = make_smb_trans_ms17_010(tree_id)
sock.put(pkt)
bytes = sock.get_once

# convert packet to response struct
pkt = Rex::Proto::SMB::Constants::SMB_TRANS_RES_HDR_PKT.make_struct
pkt.from_s(bytes[4..-1])

# convert error code to string
code = pkt['SMB'].v['ErrorClass']
smberr = Rex::Proto::SMB::Exceptions::ErrorCode.new
status = smberr.get_error(code)

print_status("Received #{status} with FID = 0")
status
end

def make_smb_trans_ms17_010(tree_id)
# make a raw transaction packet
pkt = Rex::Proto::SMB::Constants::SMB_TRANS_PKT.make_struct
simple.client.smb_defaults(pkt['Payload']['SMB'])

# opcode 0x23 = PeekNamedPipe, fid = 0
setup = "\x23\x00\x00\x00"
setup_count = 2 # 2 words
trans = "\\PIPE\\\x00"

# calculate offsets to the SetupData payload
base_offset = pkt.to_s.length + (setup.length) - 4
param_offset = base_offset + trans.length
data_offset = param_offset # + 0

# packet baselines
pkt['Payload']['SMB'].v['Command'] = Rex::Proto::SMB::Constants::SMB_COM_TRANSACTION
pkt['Payload']['SMB'].v['Flags1'] = 0x18
pkt['Payload']['SMB'].v['Flags2'] = 0x2801 # 0xc803 would unicode
pkt['Payload']['SMB'].v['TreeID'] = tree_id
pkt['Payload']['SMB'].v['WordCount'] = 14 + setup_count
pkt['Payload'].v['ParamCountMax'] = 0xffff
pkt['Payload'].v['DataCountMax'] = 0xffff
pkt['Payload'].v['ParamOffset'] = param_offset
pkt['Payload'].v['DataOffset'] = data_offset

# actual magic: PeekNamedPipe FID=0, \PIPE\
pkt['Payload'].v['SetupCount'] = setup_count
pkt['Payload'].v['SetupData'] = setup
pkt['Payload'].v['Payload'] = trans

pkt.to_s
end
end



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